This has to be one of the best investments I've ever made, barring my case to protect my baby. It folds up and fits in my case just barely, but more importantly it does what it's supposed to do - help maintain proper form. I used a foot stool for awhile but I always ended up getting a little kink in my back that still hasn't gone away completely. The thing just works - I pop it on and my guitar just sits in my lap, ready to play. The black strap on the bottom is rubberized so it doesn't slide around on your leg. I've gotten a lot of people who ask me where they can get one. I can't believe Guitar Center doesn't carry anything like it.