SP3227 Recessed Shock Sensors let you offer your customers proven shock sensor technology in a small, flush-mounted package. The SP3227 dual element Recessed Shock Sensor is installed flush with a window or door frame, so it remains unnoticed as it provides superior perimeter protection. The sensor flange can be painted to blend with any decor, so it's perfect for residential applications, and for commercial installations where appearance is particularly important. The SP3227 may also be used in pre-wire applications. Since the sensor is recessed in the window frame, it will not be damaged during completion of construction. In both the surface mounted SP3237 and the recessed SP3227, two sets of contacts must be activated simultaneously to signal an alarm. This dual contact technology reduces false alarms caused by failure of the single contact. All metal components in the hermetically sealed sensor are gold plated, eliminating corrosion from liquid or vapor contaminants.