Dropping CO2 Pressure After the Regulator?

[brdb]

My current setup is a 5lb CO2 tank with a single gauge regulator, a 2 way CO2 distributor, and 2 kegs. I was wondering if there is anything I can add (I'm assuming it would be connected after the CO2 distributor) to lower the CO2 pressure to one of the kegs. For example, I would have the regulator set at 20 PSI which is fine for one of the kegs, but I would like the other keg to be at a lower pressure (say 12 PSI). Is there something I can buy to do this? I realize a double CO2 regulator would be the best thing to get, but is there a cheaper alternative?

 

[zachattack]

You can get secondary regulators that do exactly that.

http://www.kegconnection.com/1-body-secondary-regulator-choose-taprite-or-chudnow/