This is the Great Planes ElectriFly RimFire 1.20 50-65-450 Brushless Outrunner Electric Motor. FEATURES: For Sport airplanes up to 14.5lbs (6520g) and 3D airplanes up to 9lbs (4080g) Designed for explosive acceleration and maximum torque eliminating the need for a gearbox Lightened aluminum can houses high torque rare earth Neodymium magnets Double shielded bearings Virtually maintenance-free; no commutators or brushes to wear out Two year quality guarantee INCLUDES: Great Planes ElectriFly RimFire 1.20 50-65-450 Brushless Outrunner Electric Motor Outrunner Motor Mount GPMG1210 Outrunner Prop Adapter GPMQ4909 REQUIRES: Brushless Motor-compatible 80A Electronic Speed Control Propeller: 16x8 - 18x8E SPECS: Motor Diameter: 2.0" (50mm) Motor Length: 2.6" (61.5mm) Shaft Diameter: .32" (8mm) Shaft Length: .79" (20mm) Lead Length: 3" (76mm) Connectors: Bullet type, .16" (4mm) diameter Max. Constant Current: 50A Max. Surge Current: 80A Max. Constant Watts: 1480W Burst Watts: 2360W No Load Current: 2.3A Input Voltage: 18.5-22.1V (5-6S LiPo) RPM/V (kV Rating): 450 Weight: 14.1oz (400g) COMMENTS: The three-number designation refers to Motor Diameter, Motor Length and kV Rating. jxs 4/20/06 ir/jxs update JAW 7/12/12