Do you mean little foam pieces filling a pillow insert or solid foam you cut to size? IMHO solid foam shapes need a very tailored pillow cover. JoAnns has several different grades and types of forms that allow for great variety in pillow covers. One reason I signed up for the free block of the month class on Craftsy.com was because I can make the blocks that interest me into pillow covers. I like to change mine in living and family rooms according to seasons.