... Product Description G104 Gyro /head lock gyro for rc helicopter Specifications:- Input power : 4.5-6v- Input signal ... rudder control drift one way. put your helicopter down on the ground and adjust the length ... - Fit:ALIGN TREX 450, 500, 600(battery powered) ,E-flite 400- Especial for ALGN TREX 250 ... on Trex 250, 450, 500, 600 battery powered rc helicopter for 3D flying actionwhat you waiting for?Nothing ...