These infrared photobeam curtain/barrier sensors are perfect for installation in windows, doorways, skylights, fence tops, any place where space is limited. Suitable for indoor and outdoor perimeter security, the trigger is programmable for simultaneous breaking of any single or 2 adjacent beams. The design features rugged aluminum construction, and an anti-tamper circuit for triggering an alarm if power is cut or the end cap is removed. No synchronizing wires are required and the LED alignment indicator makes installation easy. L-brackets and mounting hardware are included. FEATURES: Triggers on breaking of any single or 2 adjacent beams (programmable). Rugged aluminum construction. Weatherproof IP65 construction. Anti-tamper circuit triggers alarm if power is cut or end cap is removed. No synchronizing wires required. N.O./N.C. relay output, 1A at 12~24VDC. LED alignment indicator. L-brackets and mounting hardware included. Multi-Frequency: Reduces interference and eliminates crosstalk when multiple units are used in close proximity to one another. COLOR: Black.