Safety: to prevent children from falling out of open windows. Prevent break-ins, it can lock the window when the window is open. 2. Ventilation: Keeps indoor air ventilated and fresh. 3. Appearance: concise and pleasant surface design, solid, using high-quality materials, easy to open, suitable for all aluminum sliding doors and windows. 4. Locking does not require a key but open. 5. The secondary lock provides additional security when venting or securing your sliding door or window. This item attaches to the bottom edge of the frame or door with a small hole required. Color: Black Features: Name: Sliding window lock. Material: Zinc Alloy. Size: as shown. Color: black. Package: 1 window lock (includes accessories in the picture). Note: - Due to hand measurement, sizes shown may vary slightly. Thank you for understanding. - Depending on the brightness and light settings of the monitors, the color of the actual item may be slightly different from the pictures. The actual product is the