Spinefitter by Sissel, Back Stretcher for Lower Back Pain Relief, Back Cracking Device, Back Cracker, Upper and Lower Back Stretcher, Back Decompression Device, Lumbar Stretcher, Anthracite ROTHLEY FORCEFLEX TECHNOLOGY: Glad’s patented dual layer Length::0.75 Inch FORCEFLEX TECHNOLOGY: Glad’s patented dual layer protection is designed to give extra flex as it expands around sharp edges and heavy loads while resisting punctures 【Easy to Use】①leg compression massager with a portable handheld controller the Spinefitter helps balance your body's energy and nervous system by engaging your core muscles and specifically targeting the vertebral joints of the spine to help decrease blockages through movement SPINE SUPPORT TOOL: Gently and naturally relieve discomfort and restore natural spine alignment with the SISSEL Spinefitter