This is the Great Planes ElectriFly RimFire .80 50-55-500 Brushless Outrunner Electric Motor. FEATURES: For Sport airplanes up to 11.5lbs (5215g) and 3D airplanes up to 7lbs (3175g) 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 .80 50-55-500 Brushless Outrunner Electric Motor Outrunner Motor Mount GPMG1210 Outrunner Prop Adapter GPMQ4909 REQUIRES: Brushless motor compatible 60A Electronic Speed Control Propeller: 15x6 - 15x8 SPECS: Motor Diameter: 1.97" (50mm) Motor Length: 2.17" (55mm) Shaft Diameter: .32" (8mm) Shaft Length: .79" (20mm) Lead Length: 3" (76mm) Connectors: Bullet type, .16" (4mm) diameter Max. Constant Current: 52A Max. Surge Current: 65A Max. Constant Watts: 1154W Burst Watts: 2200 No Load Current: 1.8A Input Voltage: 18.5-22.2V (5-6S LiPo) RPM/V (kV Rating): 500 Weight: 10.5oz (298g) COMMENTS: The three-number designation refers to Motor Diameter, Motor Length and kV Rating. jxs 4/20/06 ir/jxs