Sureflote® is made from expanded low-density polyethylene foam that traps air in closed cells constructed into multi-layer membranes to create internal air pockets for added buoyancy. The Sureflote® membrane is moisture resistant and provides superior user mobility and added protection in the extreme cold. The combined jacket and pant/bib with Sureflote® provide flotation assistance for up to two hours for an average person. Just the bib or jacket will give you buoyancy and you will not float upside down while wearing just the bib.