Item Descriptions: -[Type]: This is a 17287-2RS deep groove ball bearings, size is 17x28x7mm. -[Durable Material]: Made of high-quality bearing steel, durability to deformity under heavy loads. -[Red Sealed Cover]: Double-sided closed with rubber sealing washers to protect the bearings -[Package List]: Contains 2pcs 17287-2RS deep groove ball bearings , easy to maintain. -[Application]: This type of bearing is used in the bicycle industry, such as wheel hub, headsets maintenance, which can be used for mountain bikes, road bikes, racing bike etc. -[Note]: In order to prolong the life of the bearing, do not spray water directly, otherwise the water penetration will cause premature failure of the bearing. Package: 2pcs 17287-2RS Ball Bearings (Note: Other accessories are not include.) Item Specifications: For Component:Headset,HubWheel For Bike Type:Mountain Bike,Road Racing Bike Material:Bearing Steel Colour:Silver&Red Bore Diameter:17mm0.67Inch Outside Diameter:28mm1.10Inch Width:7mm0.27Inch