Adjustable Self Heating Back Waist Support Lumbar Brace Belt Strap for Sports Working (S) Specifications: Material: Spontaneous Heat Cloth, Magnet, Elastic Strap Color: Black Package Weight: approx. 105-115g Quantity: 1pc Fit People: manual workers who long standing or sitting Size Options Apply to Wasit S 60-76cm / 23.62"-29.92" M 77-86cm / 30.31"-33.85" L 87-96cm / 34.25"-37.79" XL 97-108cm / 38.18"-42.51" Package Included: 1 x back waist supportNote: 1. First, use a clean wet towel to wipe the middle heating section of the waist support, and then fixed the waist support on the skin surface. In order to ensure personal safety, so the heat is relatively slow, generally about 40 minutes to feel the obvious heat, according to each person's physical condition, decided to wear the length of time. If after use, the skin has a hot feeling, is normal, please take off temporarily. Never damage the skin. Do not wet the waist support can also be used, but the preheating time is longer. 2. High fever, bleeding tendency, temperature sensory disturbances and damage skin are disabled. Acute soft tissue injury, please use after 24 hours. Patients with cardiac pacemakers are disabled. Individual allergies, please use under the guidance of a doctor. Such as local redness, scorching hot is normal. After the product is removed, it disappears naturally. Do not immerse in water bubble wash, gently wipe with water do not use detergent, bleach washing. Pregnant women and children are forbidden e. If you are unwell in the use, please stop using or under the guidance of use.