I use a Pellon fusible which I believe is #950. It is called ShirTailor, and was designed for collars and cuffs when making men's tailored shirts. The manager at my JoAnn's told me she's made several T-shirt quilts and that's what she uses. I'm on my second one now. Just off the bolt, it feels a little stiff, but it has a nice feel once it's fused to the fabric. I think it's regularly $5.99 a yard, and I also wait until I have a 40% or 50% coupon and buy a whole bolt.