Self-Drilling Screws with Wafer Head (C1022) Tianjin Ruiya Internation St Co., Ltd. Base Info Material:Carbon SteelType:Hexagon HeadHead Style:RoundConnection:Common BoltGrade:12.9Trademark:E-starSpecification:0.101"X1 "Origin:China Mainland Description Pre:Sanitary Manhole Cover Next:Good Quality Black Phospahte Drywall Screw Coarse Thread