BT tracking, not afraid of losing items. When the phone or other items cannot be found, you can double-click the button to trigger a prompt tone. When the item is misplaced, open the mobile app to locate it and find out where it was last detected. Automatic alarm to prevent loss: when the phone moves beyond a certain distance from the item, the device will automatically sound an alarm to remind you to take it back. Compact size, similar to a coin, easy to carry and can be placed in various locations. Two-way search function: double-click the button on the device to make the phone ring; use the app to make the device emit a sound for easy retrieval. Product parameters: Product name: Smart Object Finder Product net weight: 21g BT version: BT 5.0 Product model: Y02 Compatible systems: iOS/Android Standby time: 6 months Effective range: 15 meters Battery type: CR2032 Color: Black Material: Plastic Package contents: 3 x Smart Object Finders 1 x User Manual (English and Chinese)