Abstract: An underground shelter having a seamless housing, a lid assembly, and a latch mechanism. The seamless housing is provided with a closed bottom, a sidewall, an open top, and a shelter cavity. The lid assembly is attached to the seamless housing and extends across the open top of the seamless housing. The lid assembly has a door frame and a door assembly attached to the door frame.

Abstract: A system and a latch mechanism adapted to release a curtain for deployment along one side of a window to protect the latter against burglary. This system comprises a curtain, a latch mechanism releasably holding the curtain and including an actuation bellows, a window having a vacuum space continguous to one face thereof, a fluid line from the vacuum space to the bellows, and a vacuum pump connected to the vacuum space, whereby a loss of vacuum in the latter will expand the bellows and then triggers the latch mechanism and thus releases the curtain which deloys itself under gravity to shield the window. The latch mechanism comprises a latch finger rotatable about its longitudinal axis and including a latch pin portion pivoted at one end about a transverse axis to freely drop to a downwardly hanging released position upon appropriate rotation of the latch finger.