Standard Diameter: 1" / 1.00 InchesMetric Diameter: 25.4mmGrade: 25Material: AISI 52100 Chromium SteelBall Weight (each): 2.3617 Ounces / 66.953 GramsChrome steel balls offer the precise geometry and fine surface finish that makes them especially useful for bicycles, casters, drawer slides, door locks and many other applications.