stainless steel casting 1)three blades arrow 2)316SS 3)silica sol technique,investment casting 4)ISO9001-2008 Certificated stainless steel casting1)it is three blades arrow,also have two blades arrow2)material is 316SS,silica sol technique,investment casting3)Have passed ISO9001 certificated4)according to the electric-polishing5)it also is lost wax casting stainless steel casting