The Skirt Tube is the is the most essential building block of your AirSkirts setup. Depending on your configuration, you may require these tube in an 2, 3, 4, 6, or 8 foot lengths. Our pre-configured packages are perfect for nearly all setups but you can also buy tubes individually. Each tube is constructed with super-durable PVC Tarpaulin and heat welded to withstand years and years of use. All of our inflatables are similar in construction to military-grade inflatable watercraft and feature HC inflate / deflate valves. A .7PSI pressure release valve also prevents accidental over-inflation. Our skirt tubes also feature welded D rings on both ends so you have the option of securing them together with the carabiners and straps included in your welcome kit. Tubes weigh 4-13 pounds, so they're easy to handle. Note that our 18" tubes are not included in our standard pre-configured kits. They are used in our customized kits for motorhomes with very low ground clearance. What diameter / ground clearance do I need?