From the Manufacturer...
The Roc+ features our Plus Mold rim which allows for a smooth release when throwing the disc. The Roc+ flies very straight and stable at high speeds and has less low speed overstability than other Rocs. It slots between an Ontario and a Rancho.
Weight Range: Champion: 178-180g, R-Pro: 165-180g
Best Choice for: Straight flight, Enhanced grip, Accurate approaches
Available Plastics: Champion, R-Pro