Designed by a model helicopter flyer, the Model Avionics "Throttle Jockey" is the latest technology in rotor speed governors.
It's is a high performance, digital speed regulator designed to give optimum engine performance over the full pitch range. It uses an adaptive feed-forward control algorithm to regulate rotor speed.

The Jockey continuously adapts to the response of the engine and the demands of the pilot. Aggressive throttle commands, such as 3D flying, cause the Jockey to under-damp the control loop yielding a fast response to changing loads and slowly changing throttle commands, as in FAI maneuvers, cause the Jockey to over-damp the control loop yielding a smooth response to changing loads. 

Speed can be changed in-flight by use of an Auxiliary channel on the transmitter. OR you can adjust it manually if your radio lacks an available channel. Easy setup and installation.

Compatible with 30 size thru 90 size helis, JR, Futaba, Airtronics/Sanwa and Hitec-Z radio systems. Brackets and two 4mm magnets are supplied.

Compatible with optical sensors. Many accessories are available.

Additional information can be found at manufacturers site, including a handy online calculator to set your headspeed.