Offering forging grinding balls and high/ low/ medium chrome alloy cast grinding balls. Diameter of grinding steel ball: 20mm-150mm Roundness Of grinding steel ball made by jinan huixin: Spherical with little overfil or underfil. Breakage Guarantee: Nil breakage upon delivery Less than 1% in normal and correct operation conditions. Microstructure of forged grinding steel balls: BATTEN M + LITTLE B + LITTLE C ( M-Martensite, B-Bainitic, C-Carbide) Microstructure of cast grinding steel balls: M+ C Package of grinding steel balls: at buyer' s option ( steel drums / flexible container bags) Certificate of Qualified grinding steel balls : ISO9001-2008 For the details , pls contact emma.