Attach this item finder onto your keychain, wallet, bag, bike or purse and download the compatible app called iSearching. If you need to find the item or if the item is out of the range of 75 feet, the trackers will ring and directions will display on your phone. If you lose your phone, double tap the button on the item tracker and your phone will ring to reveal its location. Each piece comes packed in an illustrated box with instructions on back. Batteries included and are replaceable.