2-20pcs G5 Precision Ceramic Bearing Balls 1mm 15mm 2mm 25mm 3mm 35mm 4mm 5mm 6mm Si3N4 Silicon Nitride Ball Description: -These ceramic bearing balls are great for applications were there will be extreme rotation and a premium performance bearing ball is required to meet the demands. -Lighter and stronger than tungsten carbide, these silicon nitride balls are diamond polished and guaranteed not to shatter or melt in the most extreme conditions. -Higher hardness than chrome steel balls. Vickers hardness up to 1700HV. -Specially 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 English-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: G5 Material: Silicon Nitride ( Si3N4) 5mm 12pcs 2mm 10pcs 1.5mm 10pcs 3.5mm 10pcs 2.5mm 10pcs 6mm 10pcs 4mm 10pcs 1mm 10pcs 5mm 2pcs 3mm 5pcs 2mm 20pcs 1.5mm 20pcs 3.5mm 20pcs 2.5mm 20pcs 6mm 5pcs 4mm 5pcs 1mm 20pcs 5mm 4pcs 3mm 10pcs 2mm 8pcs 2mm 25pcs 3mm 25pcs _x000D_