Effectively reducing the risk of children and pets falling from heights and preventing theft. Keep your house safe, limit and fix ventilation windows to improve indoor air quality.Improved protection design: This window lock is made of solid aluminum alloy and has antioxidant and anti-aging properties. The improved vertical window lock design allows for the correct removal and storage of keys to prevent young children from accidentally opening them. Add another layer of protection to eliminate all possible hazards.Each sliding window lock can be equipped with a protective washer to prevent scratches or damage to the window. These window locks with protective plates can provide sufficient friction between the lock and the track to ensure that the window does not slide open.Easy to install: This adjustable household lock is suitable for windows and sliding doors. No hole installation saves time and effort. All you need to do is pass the key through this hole and fix the window cover onto the track. You can easily lock the window anywhere with the vertical key. No additional installation tools are required. Easy to reuse and reinstall.What you have received: 4 sets of sliding window locks, including 8 sliding window lock blocks and 4 keys, can fully meet the needs of large families and houses.