From the producer-Motion turned on, battery safety light curtains can be mounted by Velcro or magnet, uses 3 LED and 3 AAA batteries. Sylvania White LED Motion Sensor, 4.5 T x 2.5 "W x 2" D, 3 Bright White LED, On / Off / Auto Switch for 12 seconds when activated by movement, wheel Head Up & Down & Side to side, 13 'and detection range of 130 degrees, 3 Way mounting, support, Magnet, Special 100 Time Restickable 3M adhesive, supplied with 3 "AAA" batteries, indoor and outdoor use.