You can buy anywhere you want, Apple Airtag battery life and Apple Airtag device power source. If you want to visit the online store or the nearest local store. This product is readily available everywhere, in the form of a small cell battery called the CR2032. If these batteries are not available in your local shops and stores. You can find it online at Amazon, Flipkart, and many other online stores. Where you can easily find this thing.