... drywall screw material: carbon&stainless steel, brass Diameter: 3.5mm(#6),3.9mm(#7),4.2mm(#8),4.8mm(#10) bugle head drywall ... screwmaterial: carbon&stainless steel, brassCoarse thread, bugle head screw for general purpose interior wood applications Diameter ... 6" Coating: Black Phosphated,Grey Phosphated,Zinc,Yellow Zinc,Decromet Drywall Screw