Machined ront housing with four fan-style cooling holes that pump through the engine while it is runningRear threaded mounting holes with both 16mm and 19mm hole spacings fits a variety of applications. Specially designed NdFeB magnets with high temperature rating for trouble-free operationHigh Temperature 140 Celsius (356 Fahrenheit) rated wire is used for winding the motors to minimize the risk of burning the motor. High quality epoxy coated stator plates on the inner surface to prevent winding shorts. 020mm stator plate id used on this 5010 engine. High quality shielded and permanently lubricated ball bearings are used to control the motor shaft in all of our motors. High temperature adhesives are used to stator windings and prevent them from shifting and getting pinched or shorted out. 5010 360KV High Torque Brushless Motors for MultiCopter QuadCopter Multi-Axis Aircraft KV (rpm / v): 360KV Anti-tooth ESC: 20-40A Best works with props from 14-16 inch Shaft size: 4mm size:Engine size 50 x 10 mm Material:metal colour:Silver + Black Package Contents: 1 x set Brushless Motor 5010 360KV Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.