This is such a usefull tool to use when you're stencilling.
Just pour a little bit of the colour you are using into one of the 10 paint wells.  Dip just the bottom of your stencil brush into the paint and then start offloading onto the central area.
Continue offloading to a paper towel, and then start stencilling.
When you need more paint on your stencil brush, just pick up from the central area.
I can't work without this when I'm stencilling :)