... ,widely applies in the ramming bearing,the valve,the seal,measuring appliance instrument,aerospace and so on high precision ... mechanical fitting.B. Stainless steel ball:AISI316L(American),Ocr19Ni12N02(Chinese),degree of hardness≤30°,Diameter ... and so on has certain corrosive product.C. Stainless steel ball:AISI304(American),Ocr19Ni9(Chinese),degree of hardness≤30°,Diameter ...