Snap-action switches, Switches, Safety-related applications, Limit switches, Material-handling equipments, Cranes, Machinery, Industrial plants, Controlling doors, Public transport vehicles, Direct positive opening, Operation, Contacts, Safety, Lead screw limit switches, Industrial automation, Industrial installations, Auxiliary switches, Medium-voltage systems, Safety limit switches, Commuter trains, Subways, Streetcars, Busses, Normally open, Normally closed, Changeover