This is the Xerun V10 G2 8.5 Turn Modified Brushless Motor, recommended for 1/10 on-road, and off-road vehicles.

Xerun V10 G2 Motors
Specifically designed for extreme running in top 1/10 and 1/12 scale competition racing, the V10 G2 series motors and are compliant with ROAR, IFMAR, BRCA and JMRCA rules. They featuring the perfect combination of high quality materials, exquisite craftsmanship and cutting edge technology, the V10 G2 series provide the extra advantage all professional racers are looking for with minimal maintenance required.

Features:

• Designed to withstand extreme levels of use at its highest peak performance
• Complete CNC cut motor case with extra front spoke ventilation slots
• Works as a sensored motor and also sensorless without the use sensor cable attached
• Multiple steps of mechanical time adjustment from 20 to 50 degrees
• Minimal maintenance is required with precise machining technology which ensures a minimum tolerance end play of the rotor shaft. Eliminating the copper shims used in most motors.
  
• 200°C high temperature tolerance and high purity copper windings maximize conductivity and reliability
• 200°C high temperature tolerance sintered NdFeb (Neodymium, 35EH-LT) magnets
• Extreme low resistance multi-layered outlet PCB and high RPM NSK bearings
• Compliant with ROAR, IFMAR, BRCA and JMRCA rules
• Certified by RoHS, CE, FCC

Specifications:
kV: 4050
Resistance: 0.0163 Ohm
Current w/o Load: 3.2A
Max Output Power(w): 360
Current @ Max Output Power: 90A
Can Diameter: 36mm
Can Length: 52.5mm
Shaft Diameter: 3.175mm
Shaft Length: 14.6mm
Weight: 178g
Rotor: V10-Φ5-12.3