SOLD - I have for sale a medical oxygen tank type ME with built in regulator (increments 0.5, 1, 1.5, 2. 2.5, 3, 4, 5, 10, 15). The ME tanks holds 680 liters of oxygen. It has 200 psi left which means there is about 60 liters left. It also has a good hydro date till March of 2013. Completely honest you need to fill it once and that will last longer than your liver. It has an oxygen valve with cap (last picture) that allows it to be filled directly from a welding oxygen tank so no prescription needed. Both myself and another have got these tanks filled before with no problem from a gas supplier with welding oxygen. I will ship but will have to empty the tank first.