Features: Built-in thick steel plates provide strong and stable support for your back. Adjustable cross straps for extra pressure to the back. Breathable mesh fabric wicks away moisture to keep you comfortable. Adhesive fastener makes it easy to put on/take off, and adjust the tightness. Suitable for running, training, badminton, workout, gym, cycling, and other sports. Specifications: Material: Elastic fabric + Mesh + Spring + Steel Color: Black / Grey (optional) Size: M / L / XL (optional) M: Length: 90cm / 35.4in; Waist Circumference: 71-80cm / 27.9-31.5in L: Length: 100cm / 39.4in; Waist Circumference: 81-93cm / 31.9-36.6in XL: Length: 110cm / 43.3in; Waist Circumference: 94-100cm / 37-39.4in Package List: 1 * Lumbar Support