... With alarm interface .It can be linked with other security system when switch signal output. Use: Prevention for road, railway, ... main entrance and the corner♥ Security is reliable,the system adopts the high voltage,low energy design ideas, without any harm ... working mode clearly.♥ Equipped with12V, 4AH backup battery, convenient management.♥ Constant open/close, DC12V, RS 485 conjunct function when ...