LIBO Electric Bolt Lock 2 Wires Lines DC 12V Fail Safe Electronic Lock Normal Temperature for Glass Wooden Iron Door Access Control System

The original one (identical) came direct from China as it was cheap enough to take a risk on how good or otherwise it was. It is much easier to fit than most other types, just sink the active part into the door frame and the two wires to 12v dc through a switch or controller. when the 12v is off the bolt slides to the open position. Restore the power and the bolt keeps open until it senses the door is closed fully.Quite clever. Ignore the illustrated wiring diagram, that is way over the top, it just needs 12v dc and some way of switching it. I use a card reader but there are plenty of other ways to control it. My original is been working for over 5yrs