The Ronin Gear Elite Stock Harness Pack is the best tube and CO2 holder ever made! It features a comfortable waist support pack with adjustable lumbar support and elastic reinforcement straps, accessory pouch, o-ring pouch, Straight Shot style rigid squeegee holster (squeegee not included), folding Battleswab style squeegee sheath (squeegee not included), hidden key-ring, and 40 elastic loops (for use with 10-round tubes, or 12gram CO2 cartridges). Keeping your tubes and CO2 on your back helps place 'hard-points' out of the way. After using this stock harness, you'll never go to a traditional belt and suspenders again!
The Ronin Gear Elite Stock Harness Pack is older, so while it may be available used and in a few cases new, it is not commonly available anymore.