Fits 6″ & 6.5″ speakers; 3-piece foam ring speaker enhancement system–gasket mounts speaker to baffle plate surface, middle ring mounts around outer edge of speaker & circular foam pad goes behind the speaker to absorb unwanted reflections on hard surfaces such as inside a car door; Reduces panel vibration ; Increases mid-bass response ; Enhanced audio output efficiency ; Minimizes destructive wave interference ; Helps prevent front & rear wave cancellation ; Easy installation with peel & stick application ; Maximizes performance for speaker installations; Pair;