These are 3mm Silicon Nitride Ball Si3N4 Polished Ceramic Balls Grade 5. Fits many Tamiya cars including the DF01, TA01 and TA02. They are a really good upgrade for the diff, replaced the steel ball bearings with silicone nitride which can handle the heat and power of modern brushless systems. 18 in the pack so you can fill two diffs, and lose two under the fridge. Egress and Astute bearings coming soon!!
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