Giant's Cyclotron Auto II Trainer provides progressive, magnetic resistance from easy spins to burning climbs smoothly and automatically with no need for remote adjusters. The frame is foldable for easy storage and lightweight so you can take it with on the road and to races. The steel platform is super stable for those out-of-the-saddle sessions and comes with its own quick-release so set up is easy. Features: Progressive, magnetic resistance gives a wide range of resistance from easy spins to burning climbs - automatically - no remote adjuster. 100% aluminum I-Beam frame, anodized gray - stellar looks and rust-resistance. Adjustable No-Skid leveling feet. Precision-turned 50mm (2 inch) aluminum roller and 1500 gram (3+lb.) flywheel are mounted to stiff, die-cast aluminum carrier for smooth pedaling action. Tough, steel replacement quick-release skewer set included. Accommodates most wheel/tire sizes 29", 27", 700C, & 26".