NANKAI Sturdy U-shaped lock with alarm, key lock for enhanced security. - Model: HARD LOCK W6 - Color: Black - Accessories: 1 key included - Shape: U-shaped Thank you for viewing. The operation is explained in the 4th photo. 1. Key positions: "ON, OFF, OPEN" 2. "OPEN": Turn the key and place it in this position to attach/detach the U-shaped lock. 3. "OFF": Turn the key and place it in this position to lock without the alarm, and the key can be removed. 4. "ON": Turn the key and place it in this position to activate the alarm and lock, and the key can be removed. 5. If you touch the U-shaped lock and try to forcibly remove it, a loud alarm will sound. *Operation confirmed. Thank you.