On select brands, fitness machines are carefully inspected, tested, and diagnosed by our in house Fit Tech Certified Technicians. To start, they will examine the motion of the machine for unusual noises. Any system flaws discovered are repaired and/or replaced with new parts. Drive belts are replaced on all units as well as walking belts on all treadmills. All hardware, chains, pulleys, cables, and wheels are inspected and replaced as needed. Batteries are replaced, and Power cords are inspected for wear and replaced if necessary. All-Fit Tech Certified machines are sandblasted to original steel for heavy wear or sanded by hand for light scratches. They are then repainted to eliminate imperfections and prevent discoloration. The machine is then re-assembled to match factory specifications and begins to be restored to a "close to new" condition. Finally, your machine will undergo a full quality control inspection and is stress tested to ensure the highest function and durability of the product. Once the machine clears all required tests, it is professionally packaged and prepared for shipping. Fit Tech Certified Products are backed up with a Life Time Warranty on Parts and Labor