The two-speed conversion kit offers another dimension of versatility and performance for the 1st generation 1/10 scale E-Revo^® (does not fit E-Revo VXL Brushless). Choose between stump-pulling torque and blistering high-speed at the flick of a switch. The included waterproof sub-micro servo actuates the internal shift fork with the push of a button from a three channel transmitter (sold separately). The first ratio gear sets allow custom tuning for various applications and performance preferences. The close ratio first gear set is ideal for running through grass, mud bogging, and hill climbing; while the wide ratio first gear set delivers an amazing 50:1 final drive ratio for climbing serious terrain.