... .Size:various 4.Finish:zinc plated and so on NameSelf Tapping Screw MaterialLow carbon steel,Stainless SteelDiameter3.5-6.3mm Length ... zinc plated,plain,HDG,Dacromet,and so onHeadHex washer head,Phillps flat head,Phillips pan headPackingless than 25kgs bulk into carton, then ... . carriages, containers, shipbuilding, refrigeration equipments all kinds of Self Drilling Tapping Screws