This is the Great Planes ElectriFly Ammo 36-50-2300kV 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

INCLUDES

Great Planes ElectriFly Ammo 36-50-2300kV Brushless Electric Motor with connectors and four M3x5 machine screws

REQUIREMENTS

• Installing in model and connecting to speed control
  Propeller, suggested sizes include 10x7E-13x8E

SPECIFICATIONS

• Motor Diameter: 1.42" (36mm)
• Motor Length: 1.97" (50mm)
• Shaft Diameter: .197" (5mm)
• Shaft Length: .591" (15mm)
• kV Rating: 2300 rpm/V
• Weight: 8.6oz (243g)
• Input Voltage: 14.8-18.5V
• Max. Constant Current: 60A
• Max. Surge Current: 100A
• Max. Constant Watts: 1110W
• No Load Current: 2A