Monitor a segment of perimeter up to 350' long in outdoor areas (700' in indoor areas) with the Optex SL-350QDM Smart Line Photoelectric Perimeter Beam Detector. The included transmitter emits an invisible photoelectric beam that is picked up by the receiver. If anything walks between the two, breaking the beam, it can trigger your alarm system.

This set features quad-beam protection to minimize false alarms caused by birds and falling leaves. The SL-350QDM has an anti-frost design and is rated IP65 for safe outdoor use.