We are offering bolt lock. Features:fail safe type released as power off. with magnetic switch door position sensorwith dip switch for setting time delay for opening & relock doorelectric drop bolt design suitable for double swing door with 180 opening anglewith power & state led indicator low stand by current (18ma) suitable for battery backup in fail securedapplication. low working current, no over heating problem. with exit function thru low current contacts. Application:as auxiliary lock for emergency door, swing glass sheet door, frameless glass door, wooden door