High-quality material: Our security lock for sliding doors is made of aluminum alloy lock body and stainless steel lock plate, which is corrosion-resistant and wear-resistant. Durable and not easy to rust and damage, high strength, durable workmanship. Mounting : These sliding locks are installed by hole punching (hole cover), you can also choose a suitable to install this lock. Comes with Keys: Each sliding lock comes with 2 keys. When locked, simply press the lock to lock. Unlocked with a key (the key is universal) which means you need a key to open the windows or patio door. It's the to stop unwanted visitors from opening your sliding windows or patio doors outside, or keep your children from opening windows from outside. DOOR AND WINDOW SECURITY: These universal sliding door locks for interior doors are designed for most hinged or sliding doors and windows used to lock windows or restrict windows. Increase the security of your home or office. Note: Please install sliding locks on the top and bottom of the door or window for maximum security. perfect , office, kids room, nursery and primary school, providing a safe environment for children. Colour:black Material:Aluminum alloy + stainless steel Size:4.5 x 4.2cm Package Contents: 2 x child proof lock 4 x key 4 x hole plug 4 x lock piece 12 x screw Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.Products from Bazhou's store