I was looking for a good cheap hat block the other day and came across this site: http://www.franksupply.com/raffia/hatmaking-supplies.html I called them to inquire about the material the blocks were made from, and it turns out to be a polyurethane foam that is much better than the home-made gap-sealing foam block that I have been using. So, I ordered one of the 23" high dome ones Thursday and it arrived on my doorstep yesterday. It is nice and sturdy, well shaped and lightweight. I put it to quick use re-stretching an old Jackson by Bailey fur felt that I had laying around to experiment on. It works great, easy to pin to, more than sturdy enough for stretching felt on. The only bummer is the limited sizes available. When I spoke to the gentleman at the shop, he told me that they make them at their facility, the molds are rather pricey but the owner might consider increasing the size range if there was more demand. So, maybe we can create some demand.