Mushroom lock
A mushroom head locking , also mushroom head mortise interlock or mushroom pin lock is a burglar-proof window fitting , which is equipped with mushroom-head-shaped pin and, with respective locking parts after mounting an anti-jemmy. The lever protection is created when the mushroom pin on the window sash hooks into the locking part attached to the frame side.
Window fittings of a simple design are usually equipped with round heads. However, these fittings have only a low level of burglary resistance.
See also: Burglary protection
Web links
Commons : Mushroom lock - collection of images, videos, and audio files
