Using this trunk lid is easy. Just align it with your Subaru WRX or STI from 2015 - 2021 and install it according to the standard procedures. When handling, be gentle as the carbon fiber is strong but can be damaged by rough impacts. For maintenance, clean it regularly with a soft cloth and a mild car cleaner. Avoid using abrasive materials as they can scratch the glossy finish. If you notice any minor scratches, you can use a suitable carbon fiber polish to restore the shine. Also, park your car in a shaded area as much as possible to prevent the clear coat from fading due to long - term sun exposure.