Use this kit to replace damaged, worn or frozen bearings in your dolly wheels. This maintenance set fits most 1 dolly spindles. Buy one kit for each wheel.WA-BK Steel Hubs Kit includes: (2) Bearing (2) Races (1) Dust Cover (1) Grease Seal (1) Cotter PinWA-BK-A Aluminum Hub Kit includes: (2) Aluminum Hub Bearings (OD 1.98″/ID 1″) (1) Dust Cover (1) Grease Seal (1) Cotter Pin