Dual action truss rod is not the same as dual truss rods.
Usually truss rods work only one way. you can tighten it and you can loosen it. Dual action truss rod works actively in both directions.
Dual truss rods are two (probably single action) truss rods in the same neck.
Here are some instructions on adjusting the truss rod on a fodera http://www.fodera.com/FoderaAdmin/Up...justments1.pdf