This is the Castle Creations Neu-Castle 1406, 5700kV Brushless Motor. Everyone wants more power. So how could Castle improve upon the incredibly powerful CM36 series? Work with motor guru Steve Neu to change the motor from a slotless design to one with a 1.4 inch diameter slotted stator. Then change the single neodymium rotor magnet from a 2 pole donut to a 4 magnet, four pole rotor for more torque. Throw in improved manufacturing, high quality bearings and a removable end bell and you have the 1406 series of high performance motors from Castle. The end result is a motor that cranks out 30% more torque with the efficiency and durability that Castle is known for. These motors are bolt in upgrades for most all sensorless 1/10 applications and are available in the now-standard ratings of 4,600kV, 5,700kV, 6,900kV and 7,700kV.