The 834LBR (Brown) Viper Plus is a frame mountable piezoelectric sensor with a custom ACIC microchip. The sensor responds to the directly conducted energy released by breaking glass. As a result, the Viper will not false alarm from any ambient sounds, or low frequency vibrations. Additionally, the Viper can be adjusted for single or double knock response to further increase false alarm rejections. There is also a Hi-Low sensitivity jumper that is used to increase or decrease the overall sensitivity and the potentiometer is used to fine-tune the adjustment.