Below is a list of Slam Latches manufacturers from St. Louis, Missouri. Slam latches, like all latches, are a type of mechanical hardware used to close and secure doors, gates or windows. This specific type of latch is spring activated, which enables the mechanism to fasten without manually securing it. Pushing the door shut or allowing it to shut is the only action needed to engage the latch and secure the door, though the latch must be opened manually.