Soft and Stable byAnnies was the first commercial foam product (specifically made for purses, etc.) that I had the chance to try. It also has an outer shell of knit tricot, but unlike headliner, it has tricot on both sides making it firmer and able to support large size panels as well as the small.
Here it is separated from its foam core –
As with headliner, it has an outer shell of knit tricot on both sides of the foam. This combination makes it able to support larger panels that many bags will need. The tricot is fairly light weight and was easily separated from the foam. This type is made to be sewn into the seams. When I received my order of S&S, of course it was folded and had wrinkles. Using a steam iron on synthetic setting I was able to remove most of the wrinkles. After ironing, I roll the S&S into a tube shape for storage to prevent further wrinkling.
Like with the headliner, this sew in can be fused to the outer fabric using a fusible webbing. Unlike headliner, it does not matter which side you fuse to the fabric. I usually fuse a woven interfacing to the outer fabric first then fuse the S&S. The Koala bag below was made with S&S using this method.
Soft and Stable is a good product that has worked in all projects where I have used it. So if you are looking for a foam interfacing/stabilizer for many different size projects that you will be making, this would be a great choice.
S&S is most readily available in white and pre-packaged in 1/2, 1 (and some places ) 2 yard cuts and is about 58 inches wide.
Black is available at some stores online.