This exercise tool, “CoreStretch” was developed by Medi-Dyne Healthcare Products. It is an effective device for stretching your back, shoulders, hips, hamstrings, shins, etc. It comes with instructions for setting its size for you and guidelines for its use. You can get additional instructions on a DVD by going to www.medi-dyne.com. CoreStretch is light and collapsible making it easy to transport for use anywhere you go!