... 3.ISO9001:2000 Certificate precision tungsten carbide balls Precision tungsten carbide balls * High strength, high wear resistance, high precision, high temperature resistant, corrosion ... the machine industry: G5, G10, G16, G40 and G100 of JB/T 9145-1999.* Precision machined ... also available based on customers' demands.* Compatible high precision valve seats can also be made available..Carbide ...