Window restrictors for child safety, adjustable window opening size, child-safe window lock for kids and pets, easy to install and use (2 pcs, white) Adjustable Window Opening Size --- With the window restrictor, two different window opening sizes can be selected, 9.2cm and 13.5cm. The adjustable window opening size can meet daily ventilation requirements and more customer needs. Why It's Necessary --- The window lock is strong enough because it is made of polyamide material. Don't hesitate, it can prevent children from playing with windows and pinching their fingers; prevent children from falling out of windows, etc. Not only for infants but also for pets. Easy Unlock --- Press the double button to unlock the lock and the window can be opened or closed freely. No keys or other parts are missing with the lock installed. Adjust the window opening by long-pressing the slide button on the rod and sliding or pulling the window. Easy for adults to use but difficult for infants. Easy Installation Tips --- The window restrictor provides tape and screws for customers to install. With the tape, it can bear less than 26kg (the effect will be better after 24 hours). Choose the appropriate installation method based on actual requirements. Wide Range of Applications --- Used for inward and outward opening windows. Fits most windows on the market.