How to choose your size: stand in a relaxed position and measure your waist circumference at the height of your belly button (the widest part). Don't think you know your size. Don't choose by pants size. Immediate relief: Lumbar support works by supporting the spine and surrounding muscles during pain and injury. 4 built-in steel support struts provide maximum lumbar support. Along both sides of the spine, do not contact the front of the spine, and focus on protecting the lumbar spine. The flexible steel prevents the waist and back support from moving up. Support the waist muscles to relieve tension and soreness. Adjustable pulley system: double layer compression belt with fasteners can adjust the back support to the correct position and pressure according to your needs. Designed for natural movement and comfortable support Comfort you need: Made of breathable mesh, it can be worn for a long time without generating too much heat, making you comfortable when working or exercising. Grey, can be worn on or under clothes. Removable, washable, breathable, non neoprene, non elastic knitted fabric. Check the size chart in order to ensure that our back brace fits you perfectly, please be sure to check the size chart and select the appropriate size in the drop-down menu (don't assume you know your own size) Product Description Lower back support can relieve back pain We know that chronic pain, swelling, injury and discomfort will affect your mood and health, regardless of whether you have joint pain, sciatica, disc herniation, sprain and strain; Even simple tasks like walking or driving can be painful. This back support is an indispensable tool. It protects the injured lumbar intervertebral disc by limiting lumbar movement, and reduces or relieves the pain and soreness of lumbar muscles. So you can finally walk around without pain. Completely free! Lower back support Our industrial durability is made of high-quality materials, providing you with years of support Mesh material is lighter and more breathable than other materials. Product size: S size is 90cm long, suitable for waist circumference of 70-85cm. Size M is 100cm long, suitable for waist 80-95cm. L size is 110cm long, suitable for waist 90-105cm. XL size is 120cm long, suitable for waist 100-115cm.