This is the Xnova XTS 4535-525KV 4+4YY Brushless Motor, with a 6mm "Type A" 41mm shaft. The Xnova XTS series motors are developed and optimized for pure performance. The Xnova XTS series 4535 models are specially designed for 700-800mm helicopters to deliver an insane power to weight ratio. The 520kV model is recommended for extreme 3D flying and is optimized for 12S applications. All XTS motors are 100% hand-wound and each motor runs through a complete quality control test before shipping.

Features:

• Designed for extreme 3D flying
• Developed for 700-800mm helicopters
• Optimized for 12S applications
• High quality Neo Magnets, heat resistant up to 150 degree C
• Specialized wires, heat resistance up to 300 degree C
• Precise balanced
• High performance stator metal sheet
• High quality NMB bearings
• Marked leading high efficiency up to 94%
• Cooler running
• Superb quality and machining of CNC parts
• Improved torque and power output
• 1.5mm thick wire

Specifications: 
Slots & Poles: 12n10p
Winding T: 4+4 YY with 1.5mm thick wire
rpm/V: 520
Weight (without connector): 624g
Body Length (no shaft): 65.5mm
Diameter: 55.7mm
Shaft Length: 41mm
Shaft Dia.: 6mm
Mounting Holes CTC Distance: 30mm
Mounting Screw: 4x07
Max Continuous Power (Watts): 6500
Peak Continuous Power (Watts): 13000
Max Continuous Current (A): 180