This is the Astroflight 803V direct drive brushless motor and controller. FEATURES: Super high efficiency 5-turn brushless motor Powerful samarium cobalt magnets Ball bearing supported shaft Standard 1/8" motor shaft with 3/16" prop adapter Brushless Electronic Speed Control included, with BEC. Smaller and lighter than ferrite motors of similar power Designed for sport applications INCLUDES: One 020 motor with speed control, Futaba J connecter, and zero-loss battery connector. One spec sheet and warranty card SPECS: Winding: 5 turns Speed Control: 12 MOSFETs Typical Nicad: 7 to 8 cells Max Amps: 16 to 18 amps Input power: 125 to 165 watts Motor Kv: 3000 RPM/volt Winding resistance: 0.135 ohms No load amps: 1 amp Motor shaft: 1/8" diameter Prop shaft: 3/16" diameter Motor diameter: 0.95" Motor length: 1.75" Speed control: 0.9" x 1.2" Motor weight: 2.3 oz. Speed control weight: 0.8 oz. Typical prop: 6x3.5 or 5.5x4 REQUIRES: 7 cell, 500 mAh battery and Zero-Loss connector COMMENTS: Brushless motors can not handle as much current as brushed motors, due to the complexity of the speed controller. However, low current draw means these motors can use a lower capacity battery and therefore a lighter power system over all. To use this motor with an Airtronics radio, use AIRM4399 (plug kit), (adaptor wire, requires trimming the polarity tab on J connector). There is no set battery/prop/motor combination. The included spec sheet has several suggested combinations, but the modeler needs to choose his own battery and prop.