These are rubber sealed ball bearings, which offer smooth rotation, great precision of attachment and even simplified maintenance.
- 840 (4x8mm) Sealed Ball Bearings x2
- Applications include TA07 chassis pulleys, and M-chassis counter gear area.
- Using ball bearings in place of plastic and metal bearings gives better parts fit and more efficient rotation.
- These ball bearings employ rubber seals rather than metal ones – this allows you to open them up to clean and work on them.
- Low-friction oil is used to lubricate the internal workings. | 
