Based on the simple, yet magical principle that wind resistance is exponential (so the harder you pedal, the higher the resistance becomes), Schwinn developed the Airdyne, and they knew that they had something special. The AD features a smooth, air-based resistance braking system along with a pair of sturdy exercise arms for a full body workout. Its fan resistance system allows for a full range of consistent feedback and an exponential range of workout load. We carry both the standard Schwinn Airdyne and the redesigned Schwinn Airdyne Evolution, with a smaller fan and more compact size. So whether you are looking for the AD2, AD6, or Evolution, Krislynn Cycle and Fitness has it! We also carry a full line of Airdyne replacement parts and accessories (including wedge pins and a custom wind shield). Just another reason to make Krislynn Cycle and Fitness your one stop shop for all of your exercise equipment needs!