Gysum Screw Tianjin Ruiya Internation St Co., Ltd. Base Info Model NO.：GSMaterial：Carbon SteelType：Hexagon HeadHead Style：RoundConnection：Common BoltGrade：12.9Trademark：E-starOrigin：China Mainland Description Pre：Good Quality Black Phospahte Drywall Screw Coarse Thread Next：Concrete Screw/Window Frame Screw
