Hi Brad, That is a 2 Pin power supply not 4 Pin.
The requirement is 4 amps on 12v so any supply that is 12v DC with 4 AMPs or greater ability (note that a supply rating is the max it can supply so a 6A supply is not going to cause an issue) Center Pin is Positive and Barrel is negative.
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Les O'Reilly
Director - Switcher Product Management
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