The Saris Cycleops Turbo Trainer Climbing Block is a riser block that is compatible with Saris cycle trainers. Simulate hill climbs whilst training at home with this Saris accessory.  The 3-level design allows you to adjust the height of your front wheel and achieve the correct gradient for your hill climb training.  Saris Cycleops Turbo Trainer Climbing Block Features For a stable, worry-free ride with any rear wheel-mounted trainer. Stack two blocks to simulate climbing workouts. Unique 3-level design lets you select the level of difficulty: 2.1 inches (5.3 cm) 2.7 inches (6.8 cm) 3.1 inches (7.9 cm)