Specification: 1. Diameter: From 8mm to 18mm, can also make as per customer's special requirement. 2. Kinds: Low chromium, medium chromium, high medium, extremely high chromium. 3. Chemical composition: C, si, mn, cr, mo, cu, p, s We are manufacturer of grinding balls, grinding bars and other mill materials, if you have any interested in them, please contact me, i will send you our catalogue and technical date for reference.