Built-in rechargeable battery, no need AAA batteries, cost saving. Recharged by all USB devices (such as USB adapter, power bank) with charging cable included. Elegant Shell in with magnet inside, easy to install, tool free, 2 ways.WAY 1: Free adsorption on any ironwork surface, for example refrigerator, barbecue or inside the gun, WAY 2: Stick on all non-ironwork, clean surfaces with the included metal strip and double-sided tape. Portable and free to swap places per your desires. 2 lighting mode: Switch to "G": Automatically lights up when human movements are detected in darkness or at night, automatic shutdown after 20s if no motion triggers again (Will not turn on in very bright environment or during daytime); Switch to "On": Permanently on, also can be used as a flashlight or emergency light. PIR Motion Sensing.Human motion activates, AUTO Light On/Off. A perfect smart security light for cabinet, hallway, porch, wine racks, bathroom, passageway, anywhere you need lights. Suitable for family use