TomTop 30a Brushless ESC Rc Heli Motor Electric Speed Control Use top quality components to get strong current endurance. Low voltage cut-off protection / Over voltage protection / over-heat protection / throttle signal loss protection. 2 start modes: Normal / Soft, compatible with fixed-wing aircraft and helicopter. Throttle range can be configured to be compatible with most transmitters. Maximum motor speed: 210000 PRM (2 poles), 70000 RPM (6 poles), 35000 RPM (12 poles).