Esab Dual Shield II 100-D1 description: Dual Shield II 100-D1 is an all-position flux cored electrode specially formulated to weld quenched and tempered steels that require a postweld heat treatment using 75% Ar / 25% CO2 shielding gas. Dual Shield II 100-D1 was designed to weld oil field components made of 4130, 8630, API X-80 and similar steels.