Just a quick tip for those that have base sizes too large for the standard sized styrofoam heads. This one has a much larger top area and works great.
I just wanted to pass this on because my pieces would lay odd on the smaller ones and it was a pain to brush them. It also caused them to air dry strange at times because the piece wasn't expanded out all the way.
You can find them cheaper on different sites (base price), but amazon has free shipping on these on an order of $25 or more (not just on these, but total cart order if you have anything else you are in need of even non-hair related):