square head bolt 1.Grade: 4.8 -- 12.9,A2, A4 2.Size: M6-M72 3.Finish:plain, zinc plated, hot dip galvanized, dacroment square head bolt1.Grade: 4.8 -- 12.9,A2, A42.Size: M6-M723.Finish:plain, zinc plated, hot dip galvanized, dacroment4.Material:Carbon steel, stainless steel5.Packing: Standard export packing or According to customer's requirement grade 4.8 Zinc Plated square head bolt