... -quality carbon steel.Quality and price is our vantage. glass curtain wall spider Casting: investment casting ,precision casting, lost wax casting ,soluble ... steel ,alloy steel, heat resistant steel ,tool steel ,brass and aluminum ,according to DIN ,EN, ASTM, BS,JCSI.Piece numbers: small ... -ray,metallograph.Quality control: According to ISO 9001 2001 glass curtain wall spider