I have 3 platters that I use for brim blocks. One is round and 13 inches (36 cm)one is oval shaped 15 inches X 18 inches (38 cm X 45 cm) and one great BIG one that is 24 inches in diameter. (60 cm). There is a brim block I saw that I would like very much but it's way too expensive for me. These platters work well for now. You can always make the brim bigger than you want and cut it down.