JIS G3125 SPA-H is Weather steel plate, with alloy elements, such as Cu,Cr,Ni added, the anti-corrosion structural steel acquires a corrosion resistance ability and extends the service life,in the development and producing of anti-corrosion structural steel.It is a copper chromium alloy steel – this alloy displays a greater level of resistance to atmospheric weathering when compared to other unalloyed steels.