Features : Installation type: hanging mounted/surface mounted Operating: fail-safe and locked when energized Unlocking way: unlock when power-off Door type: single door Suitable for wooden, metal, glass, stainless steel and fireproof doors Wiring: PC board mounted terminal block connections Bracket is optional, assembled on hollow door and glass doors Made more secure, lock body adopts two screws on each side Can be used with access control system, building intercom and fire No mechanical damage and no residual magnetism, strong tension, less electricity and long lifespan MA certified products of China / CE certification of EU. Built-in reverse current protection device (MOV). Shell is made of high-strength aluminum alloy, Anodized. Dual Voltage 12 or 24 VDC(optional).