$20 off Viper 502M Infrared Motion Detector

Designed for use with Viper home monitoring and security system starter kits, this Viper 502M motion detector features PIR (passive infrared) technology, which senses movement from up to 39.4' away, so you can keep tabs on your home while you're out.

Features a 90° horizontal and a 105° vertical coverage area to easily detect motion within a broad expanse. Built-in tamper alarm alerts you when the unit is tilted. Sealed optics minimize false alarms due to external light, pets and insects.