2 Pack Stainless Steel Swivel Bar Door Braces, Safety Chain Retainer Chains, Recessed Steel Ball, Brushed Nickel, Comes with Screws Door locks are security devices safety lock for swing doors. They allow the door to be opened a few centimeters for safe viewing or ventilation. Child Safety Lock The secondary safety lock can also be placed out of the reach of children so that they cannot open the door themselves and enter or exit dangerous areas. Positioning of the Steel Ball Unique locking design that holds the locking arms in place so they don't swing for added security. Specification: Material: Premium Stainless Steel Color: Satin Nickel Finish: Beautiful brushed nickel process Application: Perfect for the home; Desk; hotel; motel; apartment and business How to install: 1. Choose the right location of the door and let its main body aligned with the underbody, then make marks; 2. Fix the main body to the door frame with screws; 3. Depending on the brand, secure the underbody with screws to the door; 4. Close the door and test the product. Important note during installation: 1. The door and the door frame must be at the same level; 2. If the door is concave, the gap between the door and the door frame cannot be greater than 0.5 cm; Contents: 2 x Safety Chains Door 12 x screws