MIFAB® Series MI-XHUB heavy duty shielded no hub couplings are manufactured with gaskets made from neoprene that meets the requirements of ASTM C-564 housed inside a Type 304 stainless steel corrugated shield. Four (2" through 4" size), six (5" through 15" size) Type 304 stainless steel clamps tightened with 3/8" Type 305 stainless steel hex head screws surround the shield to provide the sealing force. MI- XHUB Series Couplings are tested and certified to the ASTM-C1540-2015 and CSA B602-2016 Standards and are listed with IAPMO. The MI-XHUB are also tested and certified by Intertek Testing Services to the CAN/ULC S102.2-10 “Smoke Test". The MI-XHUB are tested by I.A.P.M.O. to comply to the FM 1680-1989 Standard (except for markings).