Abstract: The heavy iron gratings for a burglar-proof window are pivotally mounted on one side. The other side is provided with a latch type locking mechanism using a plunger having a ramped surface to hold a set of ball bearings in locking engagement with a matching cylinder. A small carbon dioxide container is mounted within the latch and is spring loaded with a detent arranged for actuation from within the home which is being protected. When the detent is released, a spring-loaded plunger punctures the carbon dioxide container, and a ramped latching plunger is moved to release the locking ball bearings, and then the iron grating or barrier is then vigorously swung open by the pneumatic pressure from the punctured container.