... and size can be customized. Cool-rolling C-steel purlin, though its small cross section, accords with ... high-efficient and can replace angle steel purlin, groove purlin, and steel bar, etc.steel purlin 1, Standard: 41x41, 41X21 ... 3m, 5.8m, 6m 4, Treatment: HDG, PG steel purlin 1, Standard: 41x41, 41X21 2, Wall thickness:1 ... etc.), single & back to back 5, Treatment: hot dip galvanized, pre-galvanized