After they’re collected, the inner tubes are checked for holes. Any blemishes that affect quality, such as punctures or glue, are removed. The tubes are then cut open, washed and stitched together, creating the bag’s weatherproof shell. Inner tubes are perfect for several reasons. First, they develop a finish over time that gives them the soft feeling of a fine Italian leather. Second, they’re 100% waterproof and virtually stain proof, so you can keep your stuff dry without worry any time of year. Any Seattleite knows how important that is.