MICRO SWITCH™ Sealed Aero Switches, Corrosion Resistant Steel - External Metals, MIL - S - 8805 symbol 3, Pin Plunger Actuator, Lead Wire Termination, 2 X SPNO Circuitry,Fine Silver Contact, 7 Amp Resistivity and 4 Amp Inductive at 28 Vdc, Plunger Seal Meterial Bentley Harris.