These special C - Cut tail light overlays are a great way to add a unique look to your Subaru WRX or STI from 2015 - 2021. Here's how to use them: First, wash your hands and make a soapy water mixture with just one drop of dish soap. Clean the area on the tail light where you'll apply the overlay and about 6 inches around it. Apply the soapy water to the back of the vinyl. This will keep it from sticking to itself and help you position it easily. Start at the bottom and work your way up. The water gives you the flexibility to lift and move the vinyl around until you're satisfied with the position. Then, just use your fingers to push out the water and air bubbles. Remember, these overlays are made in the USA with high - quality materials, so handle them carefully during installation. As for maintenance, just clean them gently with a soft cloth and mild soap from time to time to keep them looking great.