Optimize the performance of your 5” x 7” or 6” x 8” aftermarket car speakers with this RoadKill Universal Fast Rings Kit by Stinger. The RKFR5768 kit includes three foam rings that isolate the speaker and direct the sound towards the cabin to improve mid-bass response and eliminate wave cancellation. This RoadKill Fast Rings speaker enhancement system is a perfect fit for speakers and installs easily with peel-and-stick application.