The backing of the Back Posture Corrector is covered with a breathable and soft magnetic therapy fabric, implanted with millions of permanent magnetic particles. Not only is it sweat-proof, it also improves circulation, relieves fatigue and eliminates back and shoulder pain and muscle stress. This postural back support is a great entry point for those who want to try a new back support device to keep them in good, healthy posture.The adjustable back support straps provide firm, even pressure distribution across the back to control your muscles for a more comfortable fit.Specifications.The Posture Back Support is available in 4 sizes to suit most men and women of different weightsM: Waist: 80-95cm, Height: 160-170cm, Weight: 50-65kgL: Waist: 90-105cm, height 170-180cm, weight 80kg or moreL:Waist: 90-105CM, Height 170-180CM, Weight 80KG and aboveXL: Waist: 100-115CM, Height: 180-185CM, Weight: 85KG or moreXXL: Waist: 105-120CM, Height: 185-195CM, Weight: 90KG or morePacking list.1*back correction belt