There have been 3 versions of sprockets.
(1) Original Drive had stainless sprockets and an aluminum spine.
The drive was changed in many ways with the addition of plastic molded parts to reduce weight and inprove our ability to make them.
(2) The 2nd version is primarily identified by the sprocket's mast retention system. These "V1" sprockets used a set screw to hold the mast in place.
(3) "V2" sprockets have threaded masts.
