For a limited time Halcyon is offering a special: buy an single-tank Infinity system (backplate, STA, and wing) and get a doubles wing for $150.
Since the system is modular, you use the same backplate and harness with both doubles and single tanks.
To get this special, contact your local dealer. Or my partners Extreme Exposure and Dive Right In Scuba are able to help you, whatever your location! Just tell them Mer sent you for best service!