High-quality materials This anti-theft lock is made of stainless steel and is durable. It effectively protects your home, has a longer service life and provides more security for residents. Suitable for all kinds of doors This security lock is suitable for all types of doors, suitable for residential, apartment and hotel doors, it will bring you extra security Safely set window wedge This design will reduce the risk of injury to children, improve protection performance and provide reliable protection. Protect safety You can unlock the door chain lock from the inside, but not from the outside, making your apartment safer. In addition, it can help you identify the caller before completely releasing the door. Smooth surface The surface of the chain lock is smooth and shiny, not easy to scratch or fade. De plus, il peut vous aider identifier l'appelant avant de librer compltement la porte. Surface lisse La surface de la serrure chane est lisse et brillante, pas facile rayer ou se dcolorer. At the same time, it is comfortable to touch the door chain because it will not hurt your hands during use. Product description: Insurance for security knob lock with anti-lock and anti-theft function The bold chain is sturdy and durable, the chain is safe and beware of strangers Regardless of left and right, easy to install; the chute is smooth, comfortable and practical Specifications: Material: high quality stainless steel Size: see size chart Color: silver Package includes: 1 bolt 6 screws note: Due to manual measurement, please allow measurement error Due to the difference in light and display, it may cause color difference