ALVIN Ice Tubes Unique transparent PVC mailing/storage tubes in five cool colors. Ice tubes are available in 25", 37", and 43" lengths with 2-3/4" inside diameter. One end of the tube is permanently sealed while the other end allows easy access. The tubes are moisture proof and come with an adjustable nylon web shoulder strap that can clip on or off for convenience and portability. Perfect for students, pilots, contractors, draftsmen, architects, engineers, sportsmen, campers, boaters. Designed for mailing anything that can be rolled - charts, maps, blueprints, posters, etc. Protects against creases, bends, tears and folds.