Your window hinges can be a weak point that criminals might exploit to break into your home. Use this lock to secure them. When the lock is closed, it automatically engages, so the additional security does not need to be locked manually. When opening the window, the lock swings with it. Only when tilting the window does a lever need to be operated. The hinge side lock can withstand a pressure of one ton. After installation, the screws are concealed.