Shur-Lock II is a plastic coupler designed for coupling HDPE & PVC conduit. It can also be used to couple dissimilar conduits such as HDPE to PVC, threaded or non-threaded metal conduit, or fiberglass (FRP) conduit. The coupler features stainless steel band clamps (hand tightened using a 5/16" nut driver) and a locking ring. A pre-lubricated O-ring forms an air-tight seal to withstand 125 PSI on 1" - 3" sizes. ETL/UL listed for electrical installations. (Manufacturer product page and specification sheet.)