Crescent-shaped lock body: The black, long handle is ergonomically designed for comfortable grip. Turning it extends or retracts the locking point, allowing the window to open and lock.

Base and mounting structure: The oval base contains a metal mounting plate and adjusting screws, adaptable to window sashes of varying thicknesses. It is securely fixed to the window sash surface with screws.

Lock point linkage structure: The crescent lock connects to a hidden locking point. When locked, it restricts the window's opening angle, providing both anti-theft and security functions.

Core Functions

Opening and Closing Control: By moving the crescent lock body, the locking points engage or disengage with the lock seat on the window frame, allowing for smooth opening and closing of the window.

Anti-theft Protection: With a built-in lock cylinder design (on some models), the crescent lock cannot be turned after locking, effectively preventing external intrusion and also preventing children from accidentally opening the window.

Sealing Assistance: When closed, the pressure of the crescent lock ensures a tight seal between the window sash and the window frame, improving the window's airtightness, reducing air and water leakage, and enhancing sound insulation and heat preservation.