Standard Diameter: 3/8 /. Metric Diameter: 9.525mm. Material: AISI 1010 Carbon Steel. 125 Ounces / 3.531 Grams. Carbon steel balls are used in automotive applications, for semi-precision bearings, and in commercial applications such as casters, locks, and drawer slides. Other applications for carbon steel balls include locks, bicycles, roller skates, slides, trolleys and conveyors.