Some beaks are just simply foam that has been sprayed with a coat of paint. Luckl, Speck, and Mr. Magpie's beaks are made of foam but our builder has a way of giving them a "shell" hardened look with a hardening paint that helps keep its shape. I'll have to ask what it was he was using. I'm glad you enjoyed our stuff so far! There's more to come soon!What you use to make the beaks? They look really good.