Conduit Body Gasket 2-1/2″ to 3″, Cellulose, Dust-Tight Seal
https://hotfix.nsiindustries.com/product/conduit-body-gasket-2-1-2-to-3-cellulose-dust-tight-seal/
Bridgeport conduit body gaskets are used to create a seal between a conduit body and its cover. Cellulose gaskets provide a dust-tight seal, whereas neoprene gaskets are dust-tight, rain-tight and impervious to most other liquids and oils.