Hellermanntyton fittings for metallic conduit with plastic coating psc fm series hellermann tyton 166 31001 the hellermanntyton 166 31001 pcs12 is a conduit fitting with a m16 fixed external thread for plastic coated metallic conduit from the pcs fm series the conduit fitting comprises of two parts the shell and the body the connector has been manufactured from nickel plated brass hellermanntyton 166 31001 psc12 fm m16 helaguard metallic conduit screw fitting