... have class 3&class 4 conduit. Threaded both ends,with coupling Length 3.75M ... 16,20,25,32mm electrical bs standard conduit Electrical pipe, BS31 standard.Surface of class 3 ... conduit is (PG)Galvanized,class 4 conduit is(HDG)Hot dipped galvanized. Thread ... according to BS standard,15 teeth per 1". The conduit threaded both ends,one end with a coupling,another ...