The MagneTrainer Ergo Handles are designed to provide a smooth upper body workout with ergonomically designed comfort. Each handle is made from sturdy steel and contains two high quality sealed bearings to insure smooth motion and a very long life. Important! If you plan to switch back and forth between these pedals and any other pedals, we highly recommend that you purchase the MagneTrainer Quick-Connects. This will prevent damage to the pedal arms that can occur from frequently changing pedals.