Compatibility: Window locks are applicable for sliding windows, sliding doors and vertical doors. Locks are 2.4 inches long and fit tracks up to 0.4 inches wide inches with rubber cushioning or up to 0.67 inches without rubber cushioning. Please measure your track to ensure proper fitment. Quality aluminum alloy: Sliding door and sliding window stoppers: The strong aluminum will remain secure which is sturdy and strong, and the cute yellow key handle is showy and easy to be found. Double Screw In Design: Sliding window locks utilizes double screws to mount on sliding window/door tracks, prevent sliding and add more security. Simply screw them with hex keys (included) for fully secure windows/doors or to allow for ventilation, no extra tools needed. Comes with rubber cushioning to prevent scratches or damage to the window and improve window security. Widely use: Slider window locks are perfect for sliding patio doors, sliding glass doors, etc. Feel free to open the windows a few inches to get both fresh air and peace of mind, because they no longer open enough for someone to slip into your house without breaking the window and alerting your pets. Put some window lock latch to your kid's room to keep your toddler from falling out the windows.