Valve ball 1.Specialized production, 2.With advanced casting technics, 3.Conform to ASTM A105, AISI 316 and AISI 410. With advanced casting techniques and strict testing methods, we provide our valve balls to various large valve enterprises and export them to America, Canada, Poland, Italy, etc. for 7 consecutive years, with good reputation and trust from customers.Made of cast iron and stainless ...