... spider is made of stainless steel or high-quality carbon steel.Quality and price is our vantage. Casting: investment casting ,precision casting, lost wax casting ,soluble glass ... , machining, turning, milling, drilling, thread cutting.Surface treatment: glass rays electrolytic polishing, coating, varnishing, bromzing. Passivating, grinding, ... to ISO 9001 2001 stainless steel spiders,glass spider