I bought the flying geese ruler from Marti Mitchell. It shows all different sizes to go with each finished size flying geese. I also bought A, B, C, & D and a couple other sets. I've just started using them and I'm liking them a lot. I plan to buy a few more sets of them. Right now I'm working on a storm at sea pattern. There is a broken star pattern I am working on and it works out perfect for one of the pieces. It seems a little expensive but I'm looking at it as an investment. I can make all sorts of blocks with these templates and they are exact.