Handy Box Cover | Cover for Single Receptacle 1-13/32 in Dia, for 4 1/8 X 2 3/8 in Boxes | Provides Box-to-Box Connection of Knockouts; Allows Misaligned Knockout Connection by Rolling the Offset Nipple Until Aligned With Each Knockout; Hub-to-Hub Offset Is 3/4 In | Use Through Knockout to Connect Box to Conduit Coupling; Use With a Locknut to Connect Two Boxes Side by Side or Back to Back; Use With a Locknut to Connect Fixture Housings in Continuous Runs; Rigid Conduit Threads (Nps)Furbay Electric Supp