This is a bearing kit by Avid RC for the Caster Fusion EX-1.5R. We suggest that you use two of the 8x16 rubber seal bearings for the center diff because it isn't an enclosed area, this is why we have to selections for the 8x16 bearing. The bearings haven't changed through out their revisions.
EX-1.5R Factory Pro Electric
F8T Factory Pro Electric