Stopper for use in molten metal handling

In a stopper comprising a monoblock refractory body having a gas duct extending longitudinally within the body of the stopper from one end in the opposite end, the said duct providing at said one end a means of injecting gas through an aperture in the nose of the stopper and at said opposite end means for receiving a stopper support member, the improvement comprising (a) the provision of a solid gas-tight plug within the duct to seal the duct at an intermediate level within the body of the stopper to thereby form a shortened gas duct at said one end and a socket at said opposite end for receiving the stopper support means, and (b) the provision of an integral narrow gas supply channel communicating with the shortened duct between the seal and the nose and extending from said shortened duct through the body of the stopper to a gas supply inlet provided at said opposite end.