Security: to prevent children from falling out of open windows. Prevents break-in, it can lock the window when the window is open. 2. Ventilation: keeps indoor air ventilated and cool. 3. Appearance: concise and nice surface design, solid, the use of high-s, 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 added security when venting or securing your sliding door or window. This item attaches to the lower 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. Content: 1 window lock (includes accessories in the picture). Note: - As measurements are taken by hand, sizes shown may vary slightly. Thank you for your understanding. - Depending on the brightness and lighting settings of monitors, the actual color of the item may be slightly different from the photo. The actual product is the only one that can be considered standard.