Keycard Shell uses a replaceable 800 mAh BL-4C battery, designed to last for years. The battery is commonly used for older Nokia mobile phones and various other portable electronics. You can find the battery in many electronics stores or online.
note
The battery itself does not carry an independent dust or water resistance rating. Any protection against dust or moisture is provided by the device enclosure, not by the battery.
Insert the new battery into the Keycard Shell battery slot, ensuring the contacts align correctly.
2
Slide the back cover until it clicks into place.
tip
If your Shell doesn't power on when you insert the Keycard, check that your Keycard is pushed all the way, or connect a USB-C cable to charge the battery that might be empty.