Here's the story. My uncle gave me two full 20 lbs. CO2 tanks he has had for 25+ years. One is steel, the other is Al. The Aluminum has a DOT date of 2/75 /forums/images/graemlins/eek.gif. I called a local gas supply house and asked if they could test, certify, and refill the tanks. They so no, they belong to Pepsi, but you can return them to Pepsi for the initial deposit made on the tank. I say great, maybe the deposit is enough to purchase a new tank. I call the Pepsi's Special Events department here in Tulsa and tell them the situation. They told me, I could bring both bottles back and he would give me the $25 deposit on the aluminum tank but couldn't do anything for the steel tank with it being so old. After talking to him a while he said he would exchange the steel tank for a full aluminum tank for $15. Then charge $15 for each refill after that. He said this was a normal occurance to put a $25 deposit down on the bottle and exchange it when empty for $15. And if you ever want to return the bottle to Pepsi, you get your $25 deposit back - so it's basically free for the bottle and $15 for the fill! What a deal... Now I just need to know where to buy a CO2 Regulator. Any suggestions?