I bought 2 pairs of these Thunderpants and *thought* I ordered two larges. Turns out one was accidentally a small. I put it on unknowingly and wore for awhile thinking these run super small 😂 I washed and air dried so they are essentially new. Once trying the actual large pair I decided to buy more, because I LOVE them! Benefit from my blunder if you want a size small! Thunderpants 90% organic cotton/10% spandex fabric is sturdy, very stretchy, and has great retention to give our garments just enough stretch and bounce back. It helps the undies to stay up and on, and the other garments to keep their shape without sagging or bagging. We use the same soft organic cotton blend to cut our binding into a wide strip instead of using elastic so there is never any irritating elastic against your skin. All the garments are made locally and lovingly in Portland, OR.