I am a big fan of this product for making anything you want to have hold its shape when empty. I use it for bags, yarn pods, canisters, boxes....
It is easy to sew, adds practically no weight to your project, and can go in the washer and dryer.
2 sizes available:
pkg 18" x 58" and is about 1/4" thick
pkg 36" x58" and is about 1/4" thick