The 5812NT ShatterPro 3 (Rectangular Housing) detects glass breaking in a full 360 coverage pattern in an adjustable 3 to 35-ft. range. The ShatterPro 3 sensor listens for actual patterns of breaking glass, using Pattern Recognition Technology. Its coverage pattern can be easily adjusted and interference outside the range will not cause false alarms. A simple hand clap feature lets the user confirm that the sensor is operational, or a handheld tester can be activated at close range.