SPST (On)-Off Sealed Toggle Switch (1 Per Quantity) Typical applications: industrial controls marine panels trucks buses and automotive. Materials: brass terminals frame and support are steel with zinc chromate case is black phenolic plasic (flammability rating: UL 94 flame class 94V-1) and all other external parts are brass/bright nickel. Neoprene seal signifies complete protection against harsh environments. Moisture and dust resistant.