KewlFit Weight Management Vest, Black/Grey, Medium/Large Front zipper with mesh ventilation panels and adjustable side gusset for optimal fit on all body shapes Cotton material provides comfort and washability after workouts Hybrid Cooling, Uses both Evaporative Cooling HyperKewl Fabric and Removable Phase Change Cooling Packs Include one (1) KewlNeck (6698) detachable device designed to stimulate brown adipose tissue at optimal 58DegreeF temperature Include one (1) set ofCool Pax Phase Change Cooling Military Vest Inserts (7065 w/velcro) and insulated Kewler Bag