The AP950PI is a 35' passive infrared motion sensor with 80lbs pet immunity* or a 50' standard sensor. It is highly sensitive to moving infrared sources. It features superior immunity to RFI, vibration, static electricity, temperature changes, and other false alarm sources. The AP950PI is calibrated through the optics to reduce variations in sensitivity from unit to unit.The unit provides jumper-selectable sensitivity, mode, and LED settings. It’s designed to accept either the pet immune or the standard 50’ mirror provided. The masks included allow the coverage pattern to be modified for a wide variety of applications. The AP950PI sensor uses true curtain “barriers”. These infrared barriers provide uniform coverage all the way down to the floor for superior detection and “undercrawl” protection.