Can you really bring your outdoor training experience indoors? Yes you can, with this innovative riser block. Elegant, adjustable design with five different levels lets you set the height of your front wheel, simulating hill climbs up to a 6% grade. Don't feel like climbing? No problem. This riser block also simulates flat terrain. Specially constructed to enhance wheel stability and equipped with anti-slip rubber feet that stay put. Easily attaches to your trainer frame when not in use.