AB950 Airbike Oversized frame tubing and bottom bracket for added strength 27", 9-blade fan produces unlimited air resistance Simultaneous upper and lower body workout Standard, integrated windscreen prevents blowback Oversized, contoured, fully adjustable seat for maximum comfort The oversized frame tubing and bottom bracket are designed for added strength, while the 27" 9-blade fan ensures unlimited air resistance for a challenging workout. With a standard, integrated windscreen, you can focus on your workout without being distracted by blowback. Additionally, the oversized, contoured, fully adjustable seat provides maximum comfort as you exercise.