When installing adjustable shocks in the Pontiac Solstice and Saturn Sky, you must drill two large holes in the trunk to reach the adjusters. These caps cover those holes, protecting the inside of the trunk for dirt and water as well as giving the holes a more finished look.
The covers fit a 2" whole. To drill the holes in you will begin by locating the approximate area in your trunk that is over your shocks, then use a small drill bit to confirm you are centered over your adjusters. Once you find your center, drill a hole using a 2" hole saw.