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TAU® - Always-charged power bank - Charcoal Black - Compact black TAU power bank with built-in charging cables and keyring attachment. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact black keyring power bank with CES Innovation Awards 2021 badge and dual output cables (Lightning and Micro USB). - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact black power bank with smooth matte finish and attached keyring holding three silver keys. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Black TAU® power bank with metallic hook, magnetic dock, and simple wall-mount installation components. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact charcoal black power bank with integrated dual charging cables and TAU logo on strap. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact agave green power bank with built-in USB-C, Lightning, and Micro USB cables held in hand outdoors. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact white power bank with integrated lightning and USB-C cables charging two smartphones outdoors. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact charcoal black power bank connected to a phone with a short charging cable. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact charcoal black power bank with metal keyring attached, held in hand against blurred background. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact white power bank with keyring attached, held by hand on white magnetic charger panel. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Charcoal black sleek power bank in minimalistic beige TAU branded box with sliding cover and two closed boxes nearby. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact agave green power bank with built-in cable and attached keyring with keys. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact agave green power bank keyring with lightning, micro USB, and USB-C output ports. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Agave green compact TAU power bank with attached metal keyring holding three keys. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact agave green power bank with integrated charging cables and matte finish. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact agave green power bank attached to keyring held against white shirt. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Agave green power bank with metallic hook and magnetic dock shown with installation steps. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - White compact power bank with rounded edges attached to a wall charger by a keyring magnetic connector. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact agave green TAU power bank with built-in charging cables held in hand outdoors. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact white TAU® power bank with retractable cable and keyring attachment showcasing sleek minimalist design. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact white power bank with magnetic charging and integrated keyring attachment in hand. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact white keyring power bank with dual USB outputs for Lightning and Micro USB charging. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact white power bank with built-in key holder and LED indicator light. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact white power bank with integrated flat charging cables and subtle TAU logo on front. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact white power bank with rounded edges attached to black backpack by carabiner clip alongside several keys. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - White magnetic dock for TAU power bank with metallic hook and easy wall installation components. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - White compact power bank with keyring attached, held by hand, mounted on white wall for magnetic charging. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact red portable power bank with attached USB cables and keyring with keys. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact black TAU power bank with built-in charging cables and keyring attachment. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact black keyring power bank with CES Innovation Awards 2021 badge and dual output cables (Lightning and Micro USB). - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact black power bank with smooth matte finish and attached keyring holding three silver keys. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Black TAU® power bank with metallic hook, magnetic dock, and simple wall-mount installation components. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact charcoal black power bank with integrated dual charging cables and TAU logo on strap. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact agave green power bank with built-in USB-C, Lightning, and Micro USB cables held in hand outdoors. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact white power bank with integrated lightning and USB-C cables charging two smartphones outdoors. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact charcoal black power bank connected to a phone with a short charging cable. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact charcoal black power bank with metal keyring attached, held in hand against blurred background. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact white power bank with keyring attached, held by hand on white magnetic charger panel. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Charcoal black sleek power bank in minimalistic beige TAU branded box with sliding cover and two closed boxes nearby. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact agave green power bank with built-in cable and attached keyring with keys. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact agave green power bank keyring with lightning, micro USB, and USB-C output ports. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Agave green compact TAU power bank with attached metal keyring holding three keys. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact agave green power bank with integrated charging cables and matte finish. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact agave green power bank attached to keyring held against white shirt. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Agave green power bank with metallic hook and magnetic dock shown with installation steps. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - White compact power bank with rounded edges attached to a wall charger by a keyring magnetic connector. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact agave green TAU power bank with built-in charging cables held in hand outdoors. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact white TAU® power bank with retractable cable and keyring attachment showcasing sleek minimalist design. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact white power bank with magnetic charging and integrated keyring attachment in hand. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact white keyring power bank with dual USB outputs for Lightning and Micro USB charging. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact white power bank with built-in key holder and LED indicator light. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact white power bank with integrated flat charging cables and subtle TAU logo on front. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact white power bank with rounded edges attached to black backpack by carabiner clip alongside several keys. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - White magnetic dock for TAU power bank with metallic hook and easy wall installation components. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - White compact power bank with keyring attached, held by hand, mounted on white wall for magnetic charging. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact red portable power bank with attached USB cables and keyring with keys. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact black TAU power bank with built-in charging cables and keyring attachment. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact black keyring power bank with CES Innovation Awards 2021 badge and dual output cables (Lightning and Micro USB). - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact black power bank with smooth matte finish and attached keyring holding three silver keys. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Black TAU® power bank with metallic hook, magnetic dock, and simple wall-mount installation components. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact charcoal black power bank with integrated dual charging cables and TAU logo on strap. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact agave green power bank with built-in USB-C, Lightning, and Micro USB cables held in hand outdoors. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact white power bank with integrated lightning and USB-C cables charging two smartphones outdoors. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact charcoal black power bank connected to a phone with a short charging cable. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact charcoal black power bank with metal keyring attached, held in hand against blurred background. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact white power bank with keyring attached, held by hand on white magnetic charger panel. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Charcoal black sleek power bank in minimalistic beige TAU branded box with sliding cover and two closed boxes nearby. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact agave green power bank with built-in cable and attached keyring with keys. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact agave green power bank keyring with lightning, micro USB, and USB-C output ports. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Agave green compact TAU power bank with attached metal keyring holding three keys. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact agave green power bank with integrated charging cables and matte finish. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact agave green power bank attached to keyring held against white shirt. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Agave green power bank with metallic hook and magnetic dock shown with installation steps. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - White compact power bank with rounded edges attached to a wall charger by a keyring magnetic connector. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact agave green TAU power bank with built-in charging cables held in hand outdoors. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact white TAU® power bank with retractable cable and keyring attachment showcasing sleek minimalist design. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact white power bank with magnetic charging and integrated keyring attachment in hand. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact white keyring power bank with dual USB outputs for Lightning and Micro USB charging. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact white power bank with built-in key holder and LED indicator light. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact white power bank with integrated flat charging cables and subtle TAU logo on front. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact white power bank with rounded edges attached to black backpack by carabiner clip alongside several keys. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - White magnetic dock for TAU power bank with metallic hook and easy wall installation components. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - White compact power bank with keyring attached, held by hand, mounted on white wall for magnetic charging. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact red portable power bank with attached USB cables and keyring with keys. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact black TAU power bank with built-in charging cables and keyring attachment. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact black keyring power bank with CES Innovation Awards 2021 badge and dual output cables (Lightning and Micro USB). - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact black power bank with smooth matte finish and attached keyring holding three silver keys. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Black TAU® power bank with metallic hook, magnetic dock, and simple wall-mount installation components. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact charcoal black power bank with integrated dual charging cables and TAU logo on strap. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact agave green power bank with built-in USB-C, Lightning, and Micro USB cables held in hand outdoors. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact white power bank with integrated lightning and USB-C cables charging two smartphones outdoors. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact charcoal black power bank connected to a phone with a short charging cable. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact charcoal black power bank with metal keyring attached, held in hand against blurred background. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact white power bank with keyring attached, held by hand on white magnetic charger panel. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Charcoal black sleek power bank in minimalistic beige TAU branded box with sliding cover and two closed boxes nearby. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact agave green power bank with built-in cable and attached keyring with keys. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact agave green power bank keyring with lightning, micro USB, and USB-C output ports. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Agave green compact TAU power bank with attached metal keyring holding three keys. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact agave green power bank with integrated charging cables and matte finish. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact agave green power bank attached to keyring held against white shirt. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Agave green power bank with metallic hook and magnetic dock shown with installation steps. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - White compact power bank with rounded edges attached to a wall charger by a keyring magnetic connector. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact agave green TAU power bank with built-in charging cables held in hand outdoors. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact white TAU® power bank with retractable cable and keyring attachment showcasing sleek minimalist design. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact white power bank with magnetic charging and integrated keyring attachment in hand. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact white keyring power bank with dual USB outputs for Lightning and Micro USB charging. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact white power bank with built-in key holder and LED indicator light. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact white power bank with integrated flat charging cables and subtle TAU logo on front. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact white power bank with rounded edges attached to black backpack by carabiner clip alongside several keys. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - White magnetic dock for TAU power bank with metallic hook and easy wall installation components. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - White compact power bank with keyring attached, held by hand, mounted on white wall for magnetic charging. - Rolling Square
TAU® - Always-charged power bank - Charcoal Black - Compact red portable power bank with attached USB cables and keyring with keys. - Rolling Square

TAU® - Always-charged power bank

$22.90
$29.90
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Color: Agave Green
Charcoal Black
Pure White
Agave Green
Mars Red
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Designed in Switzerland

TAU 3in1 Power Bank is the world’s smallest power bank, designed to stay charged and ready on your keychain.

🔌 Universal Compatibility
Features a USB-C cable and a patented Lightning + Micro USB connector, compatible with virtually all portable devices.

🧲 Magnetic Dock
Charges automatically when placed on its dock, as seamlessly as hanging your keys.

🔋 Always Ready
Compact 3in1 design ensures your devices never run out of power on the go.

🪶 Ultra-Portable Build
Light, durable, and perfectly sized to fit on any keychain for daily carry.

TAU 3in1 Power Bank is the world’s smallest power bank, designed to stay charged and ready on your keychain.
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PRODUCT INFO


TAU® is the best 3in1 power bank, fitting the Lightning, Micro USB, and USB-C ports. It’s the smallest power bank in the world, so you can attach it to your key chain, and comfortably use it in your daily life. It’s the best portable power bank and alternative to your regular, heavy battery charger.

TAU® features a USB-C and our patented Lightning + Micro USB cable, and is compatible with virtually every portable device in the world. Thanks to its proprietary dock, charging it is as easy and seamless as hanging your keys once you get home.

Designed with love ❤️️ in Switzerland

    TECHNICAL SPECIFICATIONS

    Compatibility

    Lightning (iPhone, iPad, AirPods)
    USB-C devices
    Micro USB devices

    Technical

    Size 60x45x12mm / 2.32x1.77x0.47in
    Weight: 40g / 1.4oz
    Capacity 1400 mAh
    Holdable weight: 350gr / 12oz

    WHAT'S IN THE BOX

    TAU® Power bank

    TAU® Dock & Micro USB power cable
    Screws and wall plugs
    Nano suction double-sided layer
    User manual
    Eco-friendly packaging

    HOW TO USE
    REVIEWS
    AS SEEN ON
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    TAU® - Always-charged power bank
    $22.90 $29.90
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    ADD TO CART
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    🤔 QUESTIONS?

    Yes, TAU® is compatible with virtually every portable device that uses Lightning, USB-C, or Micro USB. It has a patented dual connector combining Lightning and Micro USB, plus a separate USB-C cable, so it covers iPhones, iPads, AirPods, Android phones, and older devices.
    It comes with a magnetic charging dock you mount on a counter or wall, and the power bank charges automatically just by placing it on the dock, the same way you'd hang your keys. That way it's always topped up and ready to grab.
    Yes, it measures just 60x45x12mm and weighs 40g, which is why it's marketed as the world's smallest power bank. It's built specifically to attach to a keychain and travel with your keys.
    No, TAU® has integrated cables built right into the power bank, so there's nothing extra to carry or lose.
    It has a 1400 mAh capacity, enough for a quick top-up on the go rather than a full multi-day charge. It's designed as a backup boost, not a substitute for a full-size power bank.
    You have two options: a repositionable nano suction double-sided layer for a damage-free mount, or the included screws and wall plugs for a permanent fixed installation. Both are included in the box, so you can choose what fits your space.
    You get the TAU® power bank, the magnetic dock with a Micro USB power cable, screws and wall plugs, a nano suction double-sided layer, a user manual, and eco-friendly packaging. Everything you need for setup is included.
    Yes, the keyring/hook is rated to hold up to 350g, which comfortably covers a typical set of keys plus the power bank itself.
    TAU® comes in Charcoal Black, Pure White, Agave Green, and Mars Red. Note that Mars Red is currently unavailable.
    It's a CES Innovation Awards 2021 Honoree and holds a 4.36 out of 5.0 rating from 1119 customer reviews. It was also designed in Switzerland.
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    Customer Reviews

    Based on 1121 reviews
    52%
    (583)
    32%
    (360)
    16%
    (176)
    0%
    (1)
    0%
    (1)
    L
    Lisa Jansen
    Perfectly portable power

    Handy and compact for emergencies.

    M
    Mike Harrison
    Perfectly portable charger

    I've always struggled with carrying bulky power banks around, but this tiny one is a game changer. Clips straight onto my keyring, and charges easily on the magnetic wall dock. Reliable and amazingly compact, absolutely love having it always at hand!

    J
    Jamie Franklin
    Amazing little charger, very happy

    Love this tiny charger, works perfectly, wish I discovered sooner!

    J
    Jake Thomas
    Handy and compact solution

    Received my charger quickly, exactly as described. I attached it to my keys and now use it all the time. Definitely recommend this handy gadget.

    123

    READ THE GUIDES

    From our editorial team — practical guides where this product fits in.

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