Material :CR-V,low carbon steel Surface:sandblasted,znc plated(Cr6/Cr3),yellow zinc plated,black oxide,black zinc plated,etc. Specifications1.Material: CR-V,Low carbon steel.2.Surface: sandblasted ,znc plated (Cr6/ Cr3), yellow zinc plated, black oxide, black zinc plated, hot dip galvanization.3.Hex socket is used to fix these hex self drilling screws by fixing this socket in pneumatic machines. ...