The single BEC supplies power for all 4 controllers

Traxxas 6756 Driveshaft

Traxxas 4030 Cylinder sleeve & piston TRX15

Engine Cooling Head SPEED B2102 - 2A304000

Traxxas 9054 Stub Axle Front (for Steel Axle #9052R) (2) Sunday-offer The single BEC supplies powerStub axle, front, 6mm, extreme heavy duty (for use with #9051R steel CV driveshafts) Upgrade your existing 9051X steel CV driveshafts to work with the Extreme Heavy Duty Upgrade Kit with these 6 mm stub axles. These upgraded axles are designed to fit the oversize bearings used in the Extreme Heavy Duty Upgrade Kit and will not fit standard axle carriers. Accessory part for these models: Hoss 4X4 VXL Rustler 4X4 VXL Rustler 4X4 Slash 4X4 Ultimate Slash