Smooth, rounded integral bushing in each hub to protect conductor insulation|Accurately tapped, tapered NPT threads for tight, rigid joints and ground continuity|Removable nipple in male sealing fitting may be used interchangeably in top or bottom hub|Restrict any explosion to the sealed off enclosure|Required in Class I, Division 1 and 2 locations within 18 in of enclosures containing apparatus that may cause arcs, sparks or high temperatures|Required in Class I, Division 1 and 2 locations where 2 in or larger conduit enters enclosure, fitting housing terminals, splices or taps|Required in Class I, Division 1 and 2 locations at the boundary where conduit leaves classified location|Required in Class I, Division 1 and 2 locations where two or more enclosures are connected by 36 in or less conduit, seal must be located within 18 in of either enclosure|Required where cables which exceed rate of gas or vapor transmission permitted for seals are used in Class I, Division 2 locations|Tapered FNPT connection|25% fill vertical conduit drain sealing fittings|Chromate/epoxy powder coated/zinc electroplated finish