After fiddling around a bit, I find that the new Orion R10 Pro is a perfect speed control for the B44.1 I have. Bought that and a TC Spec (same time) and the TC Spec already needs repair (bad capacitors, 2nd time in for repair). Also a Tekin RS Pro would be a great speed control. The last good Novak Speed control ever made was the original GTB. My brother has one that he has used for years in a b44, t4, rt5, rb5, SCT. Never an issue other then fit. Why they stopped making those I will never know.