OUR MAGNETIC BIKE TRAINER PROVIDES 5 LEVELS OF LINEAR RESISTANCE TO YOUR FINGERTIPS Easy to use, with 5 levels of smooth linear resistance, the Cascade MAGPLUS gives you a great workout. The remote shifter clamps to your handlebars, allowing you to quickly and easily vary your training routine. Backed with a LIFETIME WARRANTY, the Cascade MAGPLUS is also extremely stable. WORKS GREAT FOR MOUNTAIN BIKES Cascade bike trainers fit mountain bike tire sizes 24″- 29″. Just remove your knobby tire and replace it with a slick tire.