Replacement handle for windows with lock and alarm function. The upgrade for your windows: Replace your window handles with this lock. Double security through the lock and alarm function. The handle is suitable as a replacement for existing window handles for windows and patio doors made of aluminum, wood, or plastic to secure the opening side. The locking steel bolt withstands a pressure of over one ton. In case of attempted break-ins, a loud alarm of 110 decibels sounds. Even after installing the window handle lock, your window can still be easily opened and closed.