The "On the Edge" Series is available in three sizes
4.7x4.7 - which is great to use with Charm Pack Fabric squares - as well as layer cake fabric squares
5.8x5.8 - an "in between size" for those of you who prefer it.
and 8x8 - great for large pieces of fabric
These sets can be mixed and matched with each other, as long as all the sets are in the same size