All ductile iron self-restrained male adapters have gasket bell ends designed to push on to IPS (iron pipe size) plastic pipe. The pipe end must be beveled and lubricated with gasket pipe lube before inserting into the gasket bell end. The bell end has a factory installed pipe to fitting joint restraint to eliminate the need for thrust blocking. The inlet is MPT (male pipe thread) and designed to thread into a FPT (female pipe thread) outlet.