RDG stands for Reduced Diameter Grip.
We've reduced the grip diameter another 2mm from our standard small diameter Pro-1 Alloy Booms. To accomplish this yet retain the durability and stiffness our Alloy booms are known for, we use a special tapered tube. This allows us to use our new Fiber Composite 2-Pin Adjusting Collars and proven continuous tail-piece, providing stiffness and durability you expect from Chinook. Exceptional torsional rigidity and fits both standard and reduced diameter masts perfectly. One year warranty.