X-small Fits Waist Circum. 23.5 -27.25 (when Sizing Measure Around The Middle Of The Waist) * Provides Pain Relief And Compression For Muscle Injuries And General Lower Back Dysfunctions; Injuries To The Lumbar Discs And The Sacro-illiac Joint * Has 2 Internal Flexible Metal Stays For Support And Adjustable Elastic Side Straps * Captures Body Heat & Increases Blood Flow * Allows Skin To Ventilate And Release Moisture