This is the Viper R/C Copperhead-R ESC & VX4R.51 5150kV 4-Pole 550 Sensorless Brushless Motor Combo. The Copperhead ESC is small and offers the smallest foot print to power ratio of all the speed controls currently on the market. The Copperhead can be used in 2WD applications with VX4 4-Pole motors, but has been optimized to perform the best with VX4R 550 class 4-Pole motors in 4WD short course trucks. It comes preloaded with 5 factory preset profiles, allowing you to easily select the profile for your driving conditions, from high speed to just learning. Plus, the Copperhead features ProGauge programmability so you can easily change the parameters of the speed control to suit your needs. Additionally, all Copperhead ESC's have factory installed high capacity bullet connectors, providing easy installation and removal for cleaning and maintenance.
The VX4R 550 4-Pole Brushless motors are designed to make maximum power and torque! With the substantial weight of Pro 4 trucks you need a motor that can handle the punishment that the class is known for. The Viper VX4R.51 has been designed and tested in 4wd Short Course trucks, and has been proven to deliver the 'crazy' power you are looking for with the reliability you demand. Plus, the combo is complimented by Viper's 180 day limited manufacturers warranty for peace of mind.
VX4 Motor Specifications:
Motor Size: 550
Shaft Diameter: 5mm