3-Piece Union, Trade Size: 3-1/2 IN, Outside Diameter: 5-1/8 IN, Length: 3-1/2 IN, Flexibility: Rigid And IMC, Material: Malleable Iron, Connection: Female Threaded, Standard: UL 514B, UL File Number E14814, CSA C22.2 No. 18.3, CSA 065178 Certified, NEMA FB-1, For Connecting Threaded Rigid Conduit And IMC