This is the Yokomo BL-RS4 Drift Spec Sensored Brushless Combo. This combo combines the excellent throttle control of the BL-RS4 ESC with the consistent power of the ZERO-S Drift motor. The RS4D is a full aluminum case ESC developed in cooperation with Yokomo’s Takashiro. This ESC is great for 2WD and 4WD and features drift specific programming. In order to make it easier to control the drift angle during cornering, the throttle characteristics in the low speed range are set to mild, while the middle speed range has a little boost to produce powerful turning. Paired with this ESC is the Yokomo ZERO-S Drift 10.5 Brushless Motor. This motor is a basic sensored brushless motor ideal for drifting applications. These motors come in either black, red or purple so your motor can match your cars color scheme. The motor case has cooling vents on the can to promote better cooling of the internals. To top it off, the motor wires are already soldered in place. This motor is perfect for beginners to advanced RC drifters. The ESC can also be remotely programmed using the smartphone application and Yokomo WiFi Module (YOKBL-WM). Motor Type: Sensored/ 4Pole Sensored Brushless. Motor Limit: >5.5t (specification when using the fan). Operating Voltage: 3.7-7.4V. Full Aluminum Case/Heatsink: Yes. Rated Current per Phase: 424A. Plugged 30x30x10mm Fan: optional. BEC Output: 6V/7.4V Built-in DC Booster, Continuous Current of 3A. BEC Ouput Short Protection: Yes. “Boost 0″ Mode: Yes. Power Wires: 12 awg. Case Size: 32.9×34.6x21mm (without fan). Weight: 50g (without cables and fan).