Vandal resistant stainless steel construction, Surface mounted housing, Entry/Exit buzzer built in, Ensures Entry/Exit tone is audible to user, IP66 rated push button, Anti-tamper micro switch on lid and rear tamper to detect removal from the wall. Tamper proof lid screws, just 35mm wide suitable to install on door frames, Standard Architrave back box fixing holes for flush mounting if required. (Architrave back box and screws not included).