Brand: Hot Racing
Part Number: SMMX9390R
Hot Racing Steel Helical Differential Ring & Pinion Gear for Traxxas Mini Maxx (Rear) (39T/10T) (part #SMMX9390R), made for the Traxxas Mini Maxx. Pinion size is the easiest way to tune top speed against acceleration and keep motor temperatures in check; hardened steel lasts far longer than stock aluminum.