FAST Rings 5x7" 3-Piece Car Speaker Enhancement Kit FAST solves the problem of acoustically coupling aftermarket speakers to factory speaker openings. Its a laser cut foam product with industrial-grade, peel away adhesive backing. Get all the sound you paid for! Increase mid bass & reduce panel vibration.. The rings separate into three pieces. The first FAST Ring is a dedicated gasket for speaker mounting to the baffle plate surface. The second ring mounts around the outer edge of the speaker, just past the surround. The third circular foam pad goes behind the speaker to absorb unwanted reflections on hard surfaces, such as inside a car door. By using the 3-ring approach the kit improves the projection of the audio into the car cabin and reduces unwanted rear reflections that can degrade the sound.