Plastic insulating bushings must be used in conjuction with two locknuts when connecting threaded rigid or IMC conduit, containing no. 4 or larger ungrounded conductors, to box or enclosure.

Bushings composed entirely of plastic cannot be used to secure conduit to the enclosure. A locknut is required on the inside and outside of the enclosure in addition to the plastic insulating bushing.

Temperature rating of the plastic insulating bushing must not be less than the insulation rating of the conductors.

Always use Bridgeport's UL listed 105° C Plastic Insulating Bushings or 150° C Plastic Insulating Bushings




Note: Above comments are not an interpretation of the National Electrical Code or local regulations. Always consult your local electrical inspector for requirements in your area.


Please send your comments and questions to attn: Engineering at Bridgeport Fittings, Inc., Phone 203.377.5944, Fax: 203.381.3488 or email:eng@bptfittings.com