UHPPOTE Fail-Secure Deadbolt Electric Drop Bolt Lock 12VDC for Narrow Door

In spite of the mixed reviews, I did decide to buy this £40 unit compared to the eBay equivalent at the same price or the £120+ equivalent from a shop specialised in security.Here is my feedback :- documentation : ( * _ _ _ _ ) : as expected, the 1 pager and even the electrical schematic on the device itself is shocking and wrong ! Stick to (some of) the user feedbacks !- functionality : ( * * * * * ) : very useful to have the 2 feedback signals for door open/closed position (via a standard integral reed switch / magnet arrangement) and for the deadbolt IN/OUT position. Both signals have normally open and normally closed contacts.- quality of build : ( * * * _ _ ) : quite well manufactured and robust. However, I very much doubt that the claim for a 1000 kg resistance is substantiated !- security : ( * * * _ _ ) : do be very careful : the deadbolt can be pushed it back in with a bit of finger pressure and wiggling ! I appreciate that once the deadbolt is engaged in the strike and the door, it would take a potential burglar a lot of effort to try to push the deadbolt cylinder back in but I would have expected this risk to be have been engineered out ! However, I quite like the fact that the deadbolt is engaged (locked) when the unit is de-energised or if the 12V supply to the unit is lost (power cut) or maliciously cut. Careful, this means that the door cannot be used as a fire escape.- installation : ( * * _ _ _ ) : be careful, the deadbolt and the strike plate must be perfectly aligned : the deadbolt release action has absolutely no force whatsoever (you can prevent the deadbolt to pull out into locked position with your little finger!) so it will not lock if not perfectly aligned. The diameter of the strike plate hole is 2mm bigger than the diameter of the deadbolt.The wiring :- BLACK : Ground- RED : 12Vdc- PURPLE : the deadbolt is released (unlocked) when this wire is connected to Ground, and locked when the circuit is open- WHITE : common for the deadbolt position feedback signal- YELLOW : Normally Closed (NC) : i.e. closed circuit with COM when the deadbolt is de-energised- BLUE : Normally Open (NO) the opposite of the YELLOW !- GREY : common for the door position feedback signal (reed switch)- GREEN : (NO) i.e. open circuit with COM when the door is open- ORANGE : (NC) : the opposite of the GREEN