This video shows how to assemble the joints that attach the joystick handle to a 2-function Bondioli control valve. This hydraulic control valve, with this bi-directional joystick directly attached, is typically used on an open station (no cab) tractor and controls a front end loader. The way the joint parts attach to the two valve spools is what allows the joystick to move up and down, left and right, and in between - a bi-directional joystick, which some call a wobble stick, is a single lever that is controlling two functions. The joystick attached to the valve shown in this video is typically controlling the raise (lift) and lower functions on a tractor's front end loader (FEL) as well as the dump and tilt (retract) functions of the bucket attached to the front end loader. The way the joints are assembled allows the spools to move in and out at the same time with the movements of the single joystick, allowing oil to flow to both the loader arms and the bucket at the same time, depending on how the joystick handle is moved. The way the joints are assembled will be similar, but the parts won't be identical, on a different brand valve with the joystick directly attached.