Using this add - on is a breeze. First, make sure your vehicle has the 2” NV 2.0/Base 2.0 rack installed. If you choose the 1 - Bike Add - On, simply attach it to the existing rack to go from carrying 2 bikes to 3. For the 2 - Bike Add - On, you can quickly increase your capacity to 4 bikes. When loading bikes, be gentle to avoid any damage. Also, always double - check that the bikes are securely fastened. For maintenance, regularly clean the add - on with a mild soap and water solution. Check the bolts and connections periodically to ensure they're tight. If you notice any signs of wear or damage, it's best to replace the parts right away.