NOTICE: Compatible only when door is flush with door jamb! Secure your home or office doors with additional security with CRANACH swing bar door lock. Includes swing loop keeper, bar lock and installation screws. (1)Swing Bar door locks are security locking devices for swing-in doors, allowing the door to be opened a few inches for safe viewing or ventilation. (2)3.87” long hinged bar folds over the closed door to engage the catch, adding extra security to your swing-in door. (3)Child safe lock: CRANACH secondary security lock can also be placed out of children’s reach so they cannot open the door themselves and enter or exit into dangerous areas. (4)Premium solid metal: Swing bar lock is constructed of thicken solid aluminium alloy. It’s strong and durable, sure to last. (5)Countersunk hole design: makes the security guard lock noble and elegant. Secondary security lock has a beautiful finish to complement your lovely home decor. (6)Steel ball positioning: Unique locking design that holds locking arm in place so they will not swing around for extra security. Installation is quick and easy Step 1. Please choose the right location on your door and let its main body be aligned with the sub-body, then make marks of the screw holes. Step 2. Fix the main body to the door frame with screws. Step 3. According to the mark, fix the sub-body with screws on the door. Step 4. Close the door and test the door lock. Specifications - Material: Premium Aluminum alloy - Color: Satin Nickel - Finish: Beautiful plating process - Application: Ideal for limiting door openings and home door secure in residences, home, hotel, motel, Inn etc.