Key Switches Ace Terminal and Flat Key Switches, Mortise Cylinder Stations, Mounting Plates. KA Series Ace Terminal Key SwitchesAce round key on-off switch lock Flat Key SwitchesSingle or double bitted flat on-off key switch. MCK Series Mortise Cylinder StationsNarrow or single gang mortise cylinder key switch station… CY-1 Mortise CylindersMortise cylinder with two keys. Keyed different or alike.