The Ava bracelet has been tested for and is limited to a two-year lifetime. The battery is non-replaceable but when used properly, the bracelet's battery should last for the full two years. Do not attempt to replace the battery yourself.

To maximize battery life, we recommend that you disconnect your bracelet from the cable once it is fully charged (once the LED light turns solid green). 

The Ava bracelet including its battery is covered under a one-year warranty in the US and a two-year warranty in Europe.