R4-12.30 is an electric shock device for remotely opening left and right doors as well as double doors. It is made of zinc alloys and works with latch or ratchet locks. It can be used where a socket measuring 22 x 30 x 69 mm can be installed. The advantage of the lock lies in its small dimensions and symmetry, allowing it to be mounted on both left and right doors, as well as providing higher operational reliability even with warped door frames or misaligned doors. The symmetrical design and compact size enable its use in sliding gate systems. The R4-12.30 cover can be operated with intercom and video intercom systems on all types of entrance doors. It features a latch locking function that allows the door to be kept open permanently without using an electrical impulse, and a memory function that enables you to control the electric shock by delivering a short voltage pulse. When the latch is locked, the open state is maintained by a mechanical sensor until the door is opened.