1.material: carbon steel. 2.finish: The fasteners are yellow zinc plated. 3.size: 16.2*9.5mm. Item NameTruss Head Clinch Bolt FastenersBrand NameZhongguMaterialStainless steel, carbon steel, alloy steel .Surface TreatmentYellow zinc, nickel, zinc ,blue zinc,copper platedMOQ50000piecesDelivery Detail20~30daysPacking DetailSeaworthy package or as your requirement.Payment TermT/T, Western Union