DAX is the original one-touch winch handle design, and they have done some really neat engineering on their composite handles. They licensed the design to Lewmar to manufacture the handle in aluminum. I've used one of the Lewmar handles a few times on another boat, but just bought a pair of the DAX handles for my own boat.

On palm-grip handles, one advantage that Harken has over DAX and Lewmar is that the top knob can rotate separately from the main part of the grip.(nl)