Tamiya 15398 - JR-Double Aluminum Rollers (13-12mm) 田宮迷你四驅車迷你四驅車後備配件導輪/滾輪 雙星孖星  [15398]

With the current Tamiya Mini 4WD racing regulations, only these double rollers count as one roller. 12mm diameter roller set in the upper position and the 13mm in the lower position, improves your stability greatly and also assists cornering ability.