Align T-REX 450 Pro 3GX Super Combo Incorporates the new generation 3GX flybarless system Improved side frame design, with dedicated 3GX mounting location Brand new MX series high efficiency brushless motor, with heat sink style casing and built in cooling fan Vertical rudder servo mount design moving the CG closer to center, improving agility during 3D maneuvers High efficiency tail shaft drive dramatically reduces power loss and at the same time increases power output