[Type] : MR128-2RS deep groove ball bearings, 8mm inner diameter, 12mm outer diameter, and 3.5mm thickness. [Durable Material] : Made of chrome steel, durability and resistance to deformity under heavy loads. [Double Sealed] : Closed with double shields to protect the bearings from dust or other foreign matter, and has the features of small friction and high speed operation. [Widely Application] : The speed is about 3000 rpm, fit for medium speed toy models, fitness equipment, low-speed motors, sports equipment, etc. [Package] : Includes 10pcs deep groove ball bearings, with pre-lubricating function, easy to maintain. Item Descriptions: -[Type] : MR128-2RS deep groove ball bearings, 8mm inner diameter, 12mm outer diameter, and 3.5mm thickness. -[Durable Material] : Made of chrome steel, durability and resistance to deformity under heavy loads. -[Double Sealed] : Closed with double shields to protect the bearings from dust or other foreign matter, and has the features of small friction and high speed operation. -[Widely Application] : The speed is about 3000 rpm, fit for medium speed toy models, fitness equipment, low-speed motors, sports equipment, etc. -[Package] : Includes 10pcs deep groove ball bearings, with pre-lubricating function, easy to maintain. Package: 10pcs MR128-2RS Deep Groove Ball Bearings Item Specifications: Bearings Type:Deep Groove Ball Bearing Model:MR128-2RS Material:Chrome Steel Bore Diameter:8mm/0.31inch Outside Diameter:12mm/0.47inch Thickness:3.5mm/0.13inch Colour:Silver, Black