Wort Whipper - Super Compact Magnetic StirrerNow even more compact than ever! Measuring at just 28mm high and 120mm wide this little sucker can punch a huge amount of power through to your stir bar. Recommended Power = Low (just enough to suspend the yeast, not a super vortex) Dial up from off with the bar in the middle of your Erlenmeyer Flask until you just start to see a small vortex forming at the top, then dial a bit off that. You don't need a crazy amount of vortex to make a good starter.