Terminus Products
Recessed Shock Sensors
Terminus Shock Sensors deliver perimeter protection and are UL approved for mounting on windows, walls, roofs and safes. Ideal for residential applications, the Terminus SP3237 shock sensors contain two sets of contacts. This product has dual contact technology, which significantly reduces false alarms. Shock waves produced by an intruder cause the dual elements to momentarily bounce off the electrical contacts. All metal components are gold plated and hermetically sealed against dust and moisture to rigid ASTM standards. The SP3237 sensor is available in white, beige or brown and measures just 1 3/8" x 7/8" x 3/8".
http://www.terminusproducts.com/shock-detection/shock-sensor-products