CK-3AG11 Standard Alumina gas lens cup, part no 54N19, fits CK17, 18 and 26 type tig torches. Size 11 gas cups have a 17.5mm bore and are 29mm long

Alumina nozzles are made from high strength alumina materials, have very good electrical insulating properties; exceptionally high impact resistance, heat resistance and thermal conductivity; and resist spatter build-up. They are recommended for most welding operations except for use in confined areas.