A must-have item if you want to go fast and install a low turn / high-rpm motor.
Your drivetrain will roll more freely with these ball bearings, and your runtime per battery charge will improve as a direct result of this. I got an extra 6 minutes of runtime on my 4200mAh battery (now total of 40 minutes with a mild brushless setup like the Yeah Racing BM-0015V2 Brushless combo) just from installing these bearings - thats how good they are!
Another great thing about these bearings from Yeah Racing is that they have rubber seals, so that all the dirt stays out from the bearings and provide long lasting performance. You will probably never need to maintain or re-oil these bearings, and can spend a lot more time driving instead of maintaining your car.
Compared to other more expensive brands ball bearings I have in some of my other cars, these bearings are just fantastic. So RCMart is telling the truth - it really is a great product with ultra low rolling resistance. Buy them now for the ultimate performance in your car!