I just went and picked up a medical oxygen tank for bagging and shipping fish. They were super cheap so I picked up the other figuring some people here may need them especially at the price I paid. If you are selling fish they are a must have. The tanks were $30 each and the valve/gauge/regulator combos were $15 ea. so $45 for the whole set up. These are about 30" tall. If anybody wants them pm me, it's the only reason I bought the other 2. You can have them for what I paid for them