The YK4107 brushed version features a 550 brushed motor, while the Pro version upgrades to a 2100KV brushless motor. The brushed version has adjustable drag brake, which is not adjustable on the Pro brushless version. The Pro version also adds crawl mode and competition mode switching. In terms of part numbers, basic structural parts such as 21007 battery case and 21012 chassis frame are shared between both versions.
