There are two categories of isothermal bags: Α. those that have metallized the outer surface to repel the sun's rays and are thin, are the so-called double layer, and Β. those that are triple-layered and may be metallic on the outside, but may be made of laminated polypropylene film. The middle layer contains 1mm expanded LDPE and ensures very strong thermal insulation. Their difference is in the storage time of the food. Double layer bags ensure product maintenance for 2 to 3 hours and and triple layer bags for more than 3 hours. The isothermal bags have hard handles (right photo) with a smaller dimension of 30 cm. This means that smaller isothermal bags cannot be made.
