1-20pcs Steel Bearing Balls 13mm 16mm 17mm 18mm 19mm 25mm 30mm 35mm 40mm G10 Various Diameter Precision Chrome Steel Ball The finest quality chrome steel produced in accordance with the highest industry standards. Chrome 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. Suitable for a range of purposes, some of the most common are listed below: 1/8" is often used for clusters and old Eglish-style headsets 1/4" is often used for rear wheels and bottom brackets 3/16" is often used for front wheels 5/32" is often used for headsets with pressing cups Specification: Precision: G10 Material: AISI 52100 chrome steel _x000D_