what is the size S M L ?
THOMAS S If your feet hang off the end ,thats no big deal as long as your upper body is off the ground.
ROBERT L It only comes in one size. I'm 5 11 and it fits me perfect. I would venture to guess it fits a person 5 9 to 6 1 pretty well. Anything outside that range and you're not going to have the right body parts on the right part of the pad. But I love it!