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Taidacent Laser Ranging Sensor Module Laser Diffuse Reflection Smart Non-Contact Switch Smart Robot Obstacle Avoidance Motion Detection Infrared Switch Alarm (NPN Output)Amazon$8.99
perprokay CR123A 3V Lithium Battery 6Pack 1500mAh 3 Volt CR123, 123A, 123, CR17345, CR17335 Batteries Lithium for Camera, Flashlights, Lasers, Alarm Sensors, Optics【Non-Rechargeable】Amazon$34.99
Dahszhi Dual Laser Detector Alarm Beam Sensor Indoor 300m Outdoor 60m Infrared Detector 6.7"x3.1"Amazon$39.99
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