Alvin - Ice Tube - Purple - 37 x 2.75 Inch - Ice Tubes by Alvin are unique transparent PVC mailing and storage tubes that are designed for anything that can be rolled, including charts, maps, blueprints, and posters. One end cap of the Ice Tube is sealed closed and the other is removable. Ice Tubes are moisture proof and have removable, adjustable shoulder straps. Lead and phthalate free. The MT series is perfect for rolled documents. Alvin Ice Tubes are moisture and dust proof with an adjustable shoulder strap. 25 inch, 37 inch, and 43 inch lengths with 2.75 inch inside diameter. Alvin is one of the primary sources for drafting supplies and drawing equipment in the country. Creative Coldsnow is a pround retailer of Alvin graphic arts, drafting and fine arts products.