Includes:1 UnderCool vest1 set of cooling packsUnderCool features:Adjustable straps and a velcro front for the best fit and comfortBreathable, wicking fabrics and built-in mesh panels to keep you dry and comfortableSafe on skinBiodegradable, Non-Toxic & FDA approvedWorn under clothingSafe on skinSpecifications:4 pockets along backWeighs less than 2 lbs.Cooling relief for up to 2 hoursMachine washable (remove inserts before washing)- lay flat to dryHow to WearUnderCool cooling vest is to be worn under your clothes. You can wear virtually anything over the UnderCool! UnderCool cooling vest features adjustable straps and velcro on the front to effortlessly fit a wide variety of shapes and sizes. Four cooling pockets along the back provide cooling relief where you need it the most.1) Unfasten the hook-and-loop fastener2) Place your arms through each arm hole3) Fasten on your front tightly so the cooling packs rest firmly on your backCooling & Recharging 1) Lay the entire vest flat in the freeze or fridge2) Wait 45-60 minutes for packs to become fully solid ThermApparel UnderCool Low-Profile Phase Change Cooling Vest