B.W.P Red Tungsten Electrodes Ground Finish Assorted TIG Welding Rod WT20 2% Thoriated 1.6mm 2.4mm x 175mm (1/16" 3/32"7") WT20 2% Thoriated Tungsten Electrodes For TIG Welding. Ground Finish. Applicability: AC welding: thin-gauge aluminum and material less than 0.060" DC welding: Carbon steel, stainless steel, nickel, and titanium. Package including: 5pcs WT20 tungsten 1.6mm*175mm (1/16"*7") 5pcs WT20 tungsten 2.4mm*175mm (3/32"*7")