The GRID foam roller is designed with proprietary Distrodensity zones. This three dimensional surface has a variety of widths to replicate the feeling of a massage therapist’s hands. The GRID foam roller is for anybody who wants to move better. Use the GRID for a self-massage and roll through the tight muscles, knots and kinks that prevent feeling good and moving well. Weight tested to support up to 500 lbs/225 kg static load.