This material is not cheap! It's made with pride in the USA and then trimmed down in the USA to fit your vehicle.
It does allow light to pass through while still giving you that dark stealthy look. If matte finishes fit your theme, you should take a serious look at this mod.
They're easy to install and can surprisingly transform the look of your vehicle.
Clean and wet the surface of the overlay and the headlight using of a mixture of soap (1 drop of dishwasher soap) and water. This will help you align the piece. Place it in the appropriate area and squeegee the water out with your fingers. This will prevent damage to the surface of the overlay when you use just your fingers. You can use your nails to make sure any portion overlapping the edges sticks to the edges.
It is recommended to use a heat gun (low setting) or hair dryer to increase the adhesion of the vinyl. The soapy water decreased the adhesion so you could align it correctly. The heat will help dry out that water. For the edges, it can help you wrap the material around those edges and adhere to tougher bends at the edges.
Allow 24 hours for the overlay to fully stick to the headlight. Once completely dry, they will hold up in automatic car washes and against most power washing.
WARNING: Cancer and Reproductive Harm. (http://www.p65warnings.ca.gov)