The Sacroiliac joint and the Pelvis are the foundation of your spine (where a lot of weight is carried), and for many, it’s the source of lower back pain. This Sacroiliac Support Belt can help by applying firm, but gentle support to your lower back. By adding support to this area, your back muscles can relax, blood flow can increase and pain can be eased. Adjustable side pulls provide increased pressure to relieve discomfort. Comfortable design is inconspicuous under clothing. 3” wide. One size fits most.