Manaaki Mats are a white flat sheet that expand into a 24-cell ice pack by adding water.  Dimensions after hydration: 34.5 x 25 x 2.8cm (Length x Width x Thickness)  Weight: 800-900g   Each mat comprises of two inner textile sheets which contain the refrigerant polymer and two other high density plastic sheets which makes the product fully washable.  Once frozen the refrigerant polymer will maintain temperatures under -18°C (-0.4°F)