GEEDIAR Bike Front Wheel Riser Block Stabilize Bike Turbo Support for Indoor Bicycle Trainer Training Stationary Bikes plastic Imported It's a simple molded plastic stand for front wheel when in a static stand for bike workouts This bike riser block keeps your bicycle's front tire in place and raises the front just enough that you will not be sliding off your seat while pedaling. Internal design guarantees maximum wheel stability Anti-slip feet stay in place and eliminate handlebar vibrations Suitable for 95% size of road and moutain bikes/bicycles except Beach Cruiser