They're plastic sealed ball bearings, that provide smooth rotation, great precision of accessory and even simplified upkeep.
• 1050 (3mm Thick) Sealed Ball Bearings x2
• Applications consist of Tamiya R/C models with twin cardan joint shafts excluding Item 42363 (Axle Shafts for TRF420 Double Cardan Joint Shafts (2pcs.)).
• Using ball bearings as opposed to artificial and metal bearings provides far better rotation and better components setup.
• These ball bearings use blue plastic seals as opposed to metal people – this gives one to start the bearings to wash and work on them. Blue plastic seals in addition greatly help with preventing debris going into the battle roller.
• Low-viscosity oil is required to lubricate the inside workings.
• sometimes perform upkeep including including oil; after crashes, checking bearing movement is advised.