Window limiter safety locks are designed to limit the opening distance of doors and windows to reduce the risk of injury from falls. They also allow fresh air to enter. Suitable for most wooden, PVC, and aluminum hinges, casements, and sliding windows (horizontal or vertical). Two adjustable sizes - With our window limiter, you can choose between two different window opening sizes: 15.5cm and 18.5cm. You can adjust the door seam width to your pet's size according to your actual needs. Simply switch the round button to adjust the door spacing as desired. These window limit locks are equipped with a strong adhesive that can be firmly fixed without perforation. All you have to do is remove the protective film from the lock and stick it directly to the window or door (it will work better after 24 hours). At the same time, it is easy to remove with a hair dryer and does not damage the window surface. You will receive 2 white window limit locks for children / pets.