Ampac's 500 Series SealPAK is a 2ply laminated structure consisting of polyester and polyethylene (PET/PE). These boilable and freezable pouches can sustain temperatures from -56 to 115°C (-70 to 240°F). 500 Series SealPAKs are 4.5 mils thick, and work well with applications requiring long-term storage, sharper objects, or solutions of formaldehyde, acids, alkalies, greases, oils, and organic solvents. These transparent, airtight, and leak-proof pouches can be sterilized with gamma, infrared, and e-beam. Once sealed, these pouches can also be surface sterilized using VHP.