MaterialMade of premium aluminum alloy, durable design, spring Use a power screwdriver and drill to mount the security door lock on your door frame, complete a DIY door lock installation less than 5 minutes. Easy to match any interior swing door. Suprbird security lock to protect your home security as a door defender Easy to UsePlace your index finger on the top of the door lock and your thumb on the lock at the bottom and slide away from the base plate along the door in the direction of the hinges then pull Home Security Door LockThis lock has a spring design to prevent the child from opening the door to unknown people.Children can not easily open the door. This door lock add extra security measures for your family members while you are aways business Keep Your Home Safe4 Screws 3" Metal Construction Stop Home Security Lock designed to withstand 800Ibs of force, 12 times stronger than a normal deadbolt against kicking in. The minimum clearance required between the edge of the door frame and the wall is 30mm - ideal distance is 35mm Package Includes: 1 Door Lock Reinforcement 4 Screws 1 Instruction Notice: 1.Please allow 1-3cm error due to manual measurement. Thanks for your understanding. 2.The color of the actual items may slightly different from the listing images due to different computer screen, Thank you for your understanding. becomeveryrich