This conversion set was originally developed for the Robinson R22 and Jet Ranger, but since then it has proved to be useful for a number of other large-scale models.Please note that the matching rotor hub is not included in the conversion set, and must be ordered separately if you need it; you can continue to use the existing hub from the rotor head, Ord. No. 722/72, and this works perfectly. You therefore only need to consider replacing the hub if you need the system to look "just right".A swashplate driver is also required instead of the collective pitch compensator previously employed. You will need to shorten the pushrods from the swashplate to the blade holders to suit.Be aware that the swashplate linkage is also modified, e.g. the swashplate tilts to the left for forward flight.Rigid conversion setexcl. hub