Transit bags not only protect your Engel fridge/freezer with a layer of insulation, but they also offer a heavy-duty foil layer on the inner side that reflects direct sunlight and long wave radiation. High quality gray canvas outer layer comes with an accessory pocket and vents. The bag covers the entire unit and is easy to open – simply unzip the bag on top. The bags work with the corresponding Transit Slide Locks. Breathing holes are built in to the compressor will not over heat. Transit bags are available to fit the following models: MT17, MT27, MT35, MR040, MT45, MT60, MT60 Combi, and MT80Durable outer protective canvas Insulating and shock absorbing inner layer adds to the insulating factor of your Engel freezer. Highly reflective inner foil layer designed to reflect the long wave heat of the sun. Increases the overall performance of your Engel freezer especially if your Engel is exposed to any direct sunlight. Quality zipper allows normal access to your freezer. Plastic mesh in the right places allows your freezer to vent itself and operate normally.