4b Propellor Isolation
From ContactJuggling.org
http://www.contactjuggling.org/moves/97.gif
juggledo: This is a move where you have to have either the thumblifts or pinkylifts (ideally both) with a stack of four down pat. Your hand makes kind of a dipping motion as the balls go underneath the isolated ball. Try to learn the isolation first with three balls, it is a lot easier. Four is almost the same except it has a much faster feel in your hands, though the rotations tend to go slower. Again, it is like any isolation, you must first learn the movements so that it is almost effortless, then work to isolate a single ball in the pattern.