New high temperature phenolic connection block in mounting hood has rugged leaf spring contacts loosen two screws, rotate and remove for quick wiring|Wireless fixture unit easily threads off mounting hood for convenient servicing or for immediate exchange with stand-by unit|Specially formulated two coat baked epoxy enamel provides superior protective finish to resist corrosion|New high temperature glass reinforced phenolic socket block in fixture unit has collector ring and pin that automatically make electrical contact as fixture unit is threaded onto mounting hood|A-51 fixture units have standardized threads to fit all A-51 and mounting hoods|One hub