< p>[Durable Zinc Alloy] Made of sturdy zinc alloy for long-lasting durability. Complete with all components for easy installation. [Easy Installation] Fits all sliding glass doors for quick, convenient, and time-saving installation. Slot size: 197 x 28 mm. Applies to doors and windows with hollow interior materials, NOT solid wood doors. Single-sided locks are only suitable for single-sided slotted doors and windows. [Smooth One-Sided Closure] Smooth operation with a single-sided hook lock for reliable security. [Installation]: 1. Determine the location. Size: 197 x 28 mm; 2. Determine the direction and secure the hook with screws. Screw the board firmly (do not drop it, leave some slack). 3. Align the side with the lock hook with the side slot and insert the lock assembly at an angle. 4. Secure the one-sided lock directly with screws. 5. Install the lock hook seat according to the hook position.