2-1/2 lb. Steel CO2 Cylinder, Empty

2.5 lb. Steel CO2 Cylinder, Empty How many kegs of draft beer can be dispensed out of a CO2 tank?  Where can I get a CO2 cylinder filled? Specifications: Material Steel Capacity 2-1/2 lbs. Diameter 3-1/2" Height 18-1/4" Weight (Empty) 6-1/2 lbs. Valve Threads CGA-320 (Intended for use with a CO2 Regulator) Notes: Round bottom, will not stand upright without support.