I received my Smart Ball and proceeded to nearly blow my lungs out trying to inflate the ball. Oddest thing I ever saw, has a valve like a beach ball, but it does not function like a valve on the beach ball. After 15 - 20 minutes to blow up a small 6-8" ball, I tried it and love it. I sent an email; to the company asking why it was so hard to inflate, and never received a reply. I think it is a good training device, but it is a hassle till you figure it out.