YOKOMO CERAMIC BALL BEARING OF TRANSMISSION CASE FOR YD-2 SERIES (Y2-BBCMA) This is a ceramic bearing set for all chassis in the YD-2 series. With these high grade bearings, it is possible to obtain the ultimate rotational efficiency by using ceramic balls in the bearings for precision and maximum durability. The kit will consist of 6 x 1050 bearings and 2 x 1510 bearings required for the 4 gear transmission of the YD-2 , ultimately improving throttle response and top speed.