Spektrum Firma Sensorless 3300kv Brushless Motor. 

Specifications:

• Operation Voltage: 2S-3S/12.6V
• RPM/Volt: 3300kv
• Current@12V: 4.5+/- 1.0A
• Maximum Continuous Current: 33A
• Output: 430W (2S)/780W (3S)
• Efficiency: 82%
• Motor Diameter: 36mm
• Motor Length: 52mm
• Weight: 200g
• Shaft Extension Length: 15mm +/-.5mm
• Shaft Diameter: 3.175mm
• Rotor Type: 4 Pole
• Plug: 4mm Male Bullet
• Extension Wire Length: 120mm +/-10mm