Welding Consumables GTAW [TIG Rod] Mild steel & 490MPa high tensile steels Product AWS JIS EN ST-50G A5.18/ASME SFA5.18 ER70S-G Z3316 YGT50 1668 - W3Si1 ST-50.6 A5.18/ASME SFA5.18 ER70S-6 Z3316 YGT50 1668 - W3Si1 ST-50.3 A5.18/ASME SFA5.18 ER70S-3 1668 - W2Si ST-72 A5.18/ASME SFA5.18 ER70S-2 Z3316 YGT50 ST-1N A5.28/ASME SFA5.28 ER80S-Ni1