The dash opening this kit is made for is a different shape and size than typical aftermarket car stereo receivers. The dash kit covers the "gaps" and the mounting brackets secure your new receiver in the dash.
Note: If you are installing a DIN-style receiver, you'll need to convert the 2-shaft face plate to accept your radio by cutting and removing the plastic shaft supports.
The kit includes:
brackets, to mount the kit into the dash
trim ring, to cover gaps between your new receiver and the dash opening