This is the Great Planes ElectriFly Ammo 12-30-4110kV Brushless In-Runner Electric Motor. FEATURES: Brushless, slotless Ammo In-Runner Motors offer an incredible power- to-weight advantage and almost twice the efficiency of Brushed motors Ideal for direct or gear drive use Up to 89% efficient and virtually maintenance-free; no brushes to wear out Powered by "rare earth" Neodymium magnets for high torque and unmatched heat resistance Pre-installed gold plated connectors for plug and play operation when used with compatible ElectriFly Silver Series Brushless speed controls Double sealed bearings Two year warranty INCLUDES: Great Planes ElectriFly Ammo 12-30-4110kV Brushless Electric Motor with connectors and four M1.5x5 machine screws REQUIRES: Installing in model and connecting to speed control Propeller, suggested sizes are 7x4S-9x4.7S SPECS: Motor Diameter: .472" (12mm) Motor Length: 1.18" (30mm) Shaft Diameter: .059" (1.5mm) Shaft Length: .335" (8.5mm) kV Rating: 4110 rpm/V Weight: .6oz (16g) Input Voltage: 7.4-11.1V Max. Constant Current: 2.1A Max. Surge Current: 4.5A Max. Constant Watts: 22.2W No Load Current: .3A jxs 2/23/06 ir/jxs