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.