FEATURES:• Freud router feature superior quality ball bearings.• Lubricated with high temperature lubricant to withstands the stresses of turing at 22,000 RPMs.• Shielded to keep out unwanted wood dust and ships that greatly reduce bearing life.SPECIFICATIONS:• Overall Diameter: 3/8"• Bearing Diameter: 3/8"• Minor Height (m): 1/8"• Bore Diameter: 3/16"Repairing and altering the profile of Freud router bits. Will fit most brands of router bits.