Wire conduit liner. Steel liner for Bernard style 400 - 500 amp Mig welding guns. Insulated 25' steel liners for Bernard 20' and 25' welding guns are easy to install and trim to fit. Properly sized and maintained wire conduit liners help keep welding wire feeding smoothly and shielding gas flowing. Wire condiut liners are made in the USA. Steel wire conduit liner for Bernard style 400 - 500 amp Mig welding guns ship the next business day.