What is the Mueller Back Bracesuitable for everyday use in the treatment & prevention of low back pain. Lightweight & comfortable, it features eight flexible steel springs for support of the lower back. When can I use it? For general back ache & conditions such as: Sciatica Herniated Disc Spinal Stenosis Facet Syndrome Degenerative Disc Disease Lumbago Great for use during severe & recurring cases of back pain. Ideal for the office, driving or when sitting at home. Which size do I need? Measure around the waist. If you are between sizes, please choose the larger size. One size fits most. Fits waist sizes 71-111cm (28-44). How does it work? The Mueller Back Brace is an elasticated back support with a non stretch fabric back panel & Velcro fastening that helps provide support for the lower back. Eight flexible steel springs in the back panel provide stability & support for the lower back. Adjust to the desired level of support using the high quality Velcro fasteners, the Back Brace acts like a corset to re-enforce the spine & torso. The flexible steels springs improve posture by preventing a slouched position. By keeping the lower back in an upright or extended position there is less strain on the muscles, ligaments, discs & nerve roots. This relieves back pain.