The Atlas is an overmold Mid-Range with a small amount of high speed turn and very little fade. XT is a tough plastic blend that was originally developed for the Nova and Atlas. It worked so well, it spread to other models. Grip is off the charts and durability is almost as good as our premium plastics. XT is firmer than R-Pro, and less firm than KC Pro with a unique grip that feels great in the hand, and inspires confidence when throwing.