H08A: For submerged arc automatic welding of carbon steel, low alloy steel and corresponding strength grade steel for pressure equipment. H08MnA: For welding of carbon steel, low alloy steel and corresponding strength grade steel for pressure equipment with flux SJ101. H10Mn2: For submerged arc automatic welding of 500MPa grade carbon steel, low alloy steel and corresponding strength grade steel for pressure equipment. H70S-E: For welding of Q355C low alloy high strength structural steel.