Charge Ninja is the name of a new highly portable battery pack for smartphones, including iPhone and Android devices, that’s raising money on Indiegogo. The Charge Ninja is about as big as a credit card, although thicker, and will easily fit inside wallets, small pockets and purses, waiting to deliver up to 85% (or 1,500mAh) of an iPhone 5s battery charge.

The device is also compatible with other gadgets that can be charged using an USB port, including tablets, portable game consoles and Bluetooth headsets.

The cheapest Charge Ninja costs $29 via Indiegogo, and should ship at some point in December, assuming the project is funded. The company is looking to raise $21,000 by October 8th to make the Charge Ninja an actual product.

In addition to the credit card-sized charger, backers will also receive a special Charging Key that’s used to connect the Charge Ninja to a smartphone or laptop (a $10 additional charge is required for Lightning iPhone cables), and which can be easily attached to a keychain when not in use.

A video showing the Charge Ninja in action follows below.