SAFE: This window block keeps the window open in a narrow area and helps the child stay safe around a sliding door or window. Adjustment window lock: The clamping distance is between 2.5 and 4 cm and the groove height is better than 1.5 cm for maximum function of the lock. High quality: Our anti-theft window locks are made of aluminum alloy, durable and thick. And it has non-slip silicone pads to increase the strength. DESIGN: Adopt rubber coating design, increasing the edge, will not scratch the window or door. Easy to install: No additional tools are required and no drilling is required. Open the windows to the right position or close the windows according to your needs.