I worked in a medical office and was always able to get the adult sized tongue depressors - they are the perfect size for making fillets. Well, I retired and had to find another source. The tongue depressors sold at JD are pediatric sized. They are okay for mixing epoxy and scraping out containers, but much too small to do any fillet work with.
A box of stir sticks are always in my shop. I don't have time to hunt around for scraps of wood when I'm painting or working with epoxy. A box of these things are there when needed, always clean and strong enuff to the job. Hard to find anywhere else.