These new bags are extremely popular internationally. They not only protect your Engel freezer with a cushion layer, but they also offer added insulation for extreme conditions. The outer layer is made of a high quality gray canvas with an accessory pocket and ventilation holes. The bag covers the entire unit. Access to your freezer is easy - simply unzip the bag on top. (The bags work with the corresponding Transit Slide-Loks.) In addition, the bags have a reflective layer on the inner side, offering top heat protection from direct sunlight, and long wave radiation.