Kogel Speed Kolossos for Shimano GRX 2x (11 & 12-Speed, Mechanical & Di2): The Fastest Oversized Derailleur Cage for Gravel Gravel doesn’t mean slow. The all-new Kogel Speed Kolossos for Shimano GRX 2x (11 & 12-speed, Mechanical & Di2) is designed to bring unmatched efficiency and performance to mixed terrain riding. Whether you're racing gravel, tackling epic adventures, or just looking for a smoother, more efficient drivetrain, this oversized derailleur cage is built to optimize every watt. With a sleek, aerodynamic design tailored for gravel speeds, the Speed Kolossos reduces drivetrain drag while maintaining the durability and crisp shifting Shimano GRX is known for. The custom-machined cage and oversized ceramic pulleys minimize friction, helping you ride faster and longer with less effort—no matter how rough the road gets. If you’re looking for next-level efficiency on gravel , the Speed Kolossos for Shimano GRX 2x delivers. Smoother, faster, and built for the long haul—because speed isn’t just for the road.