The original bmax2mr ball diff is 12 ball (part no. B2-500MR). The newer YZ2 Z2-500 ball diff is 14 ball and much more durable, but other than that they are the same.
If you have the older type, and replacing balls, its worthwhile getting the newer (Z2-503) 14 ball gear as its definitely worth the upgrade for how much smoother and longer it lasts.
Otherwise, plates, thrust, outdrives, spring, bearings and bolt are the same.
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Team Yokomo - YZ-2CAL3 | YZ-2DTM3 | YZ-4SF2 | YZ-2T | YZ-2DTM Worlds | YZ-2DTM x2 | YRX-12 x2
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10electric | Batley Buggy Club | YORCC | RHR | MB Models
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