Originally designed for the Olympic Games security detail. This device is extremely sensitive, detects guns, knives, razor blades, box cutters, foil wrapped drugs, and even the smallest objects. Features audible or silent alarm. LED indicators for power, alarm and battery. Rugged high impact ABS case with reinforced coil compartment. Runs on single 9V battery (included). Provides up to 100 hours of use. Made in the USA. Size- 3 1/4" x 1 3/4" x 16 1/2".