For optional 2-speed high/low transmission - Use the included blue gears to maintain stock vehicle speed in high gear and crawling speed in low gear

They give the 1

Traxxas 9739-ORNG Servo Mount Alu Orange TRX-4M

Dimensioner: 14

FUTABA 103077 TX FM35

Du-Bro 133341 - Long Dual Servo Arms (JR) 2/pkg DF65 lipo For optional 2-speed high/low transmissionA new servo arm design for large aircraft. This dual arm allows for straight and in line movement of the control surface. Made of long fiber composites, this arm is super strong and will provide the maximum security. The Long Dual Servo Arms include heavy duty ball links for 4 40 pushrods and assembly hardware. The arms have 3 mounting holes for increased or decreased servo throw. Fits: JR Dimension from center to the end mounting hole is 34. 13 mm 2