I was asked to explain the "difference", between the RW Springer drive mechanism and the "stock" drive mech on the RW-KD, most of us know the difference between Adjustable Give and no Give......The Springer is not infinitely adjustable, like some other Rotaries,but, it covers most tasks admirably... http://www.youtube.com/watch?v=NiDNf...ature=youtu.be