Instructions: 1.High efficient brushless motor for large electric helicopter, use 6cell Li-Po to perform super torque and power, great economical and efficient choice. 2.The 600L is maintenance free, and has a light, compact design. Gilt terminals are included for simple connection with ESC. The motor operates with very high efficiency, and low power consumption. The motors will provide many hours of smooth, reliable, quiet, and efficientflying. 3.These new brushless motors are designed with a new radiator system. The motors are built with an integrated cooling fan and has air ingress/egress vents, circulating cool air inside the rotor continuously. The motors efficiently lower operating temperature. 4.The motors feature High-speed ball bearings, powerful magnetic outrunner rotor.