Design: Thick stainless steel chain design tight chain twist welding combination durable and not easy to break can be used for a long time. Anti theft: Anti theft steel chain can enhance security and provide reliable intrusion protection spring buttons to enhance protection and can not be unlocked outside thus making you more secure. Easy to install: Two installation methods use nail-free glue without punching or fix with screws The door lock can be used on wooden or metal doors on various types of doors and it can be placed above or beside the door panel . The door latch is very easy to install and strong. Application: Door chain lock suitable for opening and closing of inner doors sturdy and durable and can be widely used for security and anti-theft of homes hotels apartments and courtyard doors. Security Locking: There is a button with a spring anti-theft press lock. The chain can be opened by pressing the safety buckle which effectively prevents outsiders from reaching into the inner hook and falling off the chain. This design can let your chain fall and protect your house more intimately. Specification: Product name: door chain Color:black silver red ancient Material: stainless steel Chain length: about 160 mm/6.30 inches Size: (L*W) short: about 71*30 mm/2.80*1.18 inches long: about 123*21 mm/4.84*0.85 inches Package Includes: 1pc*door chain 4pcs* screws 1pc*no nail glue