The Stinger 3-piece foam ring speaker enhancement system solves the problem of acoustically coupling aftermarket speakers to factory speaker openings. The RoadKill Fast Rings kit increases speaker output, improves the projection of the audio into the car cabin and reduces unwanted rear reflections that can degrade the sound.
3-piece Foam Ring System fits 5" & 5.25" Speakers

Specification:

• Reduce panel vibration 
• Increase mid-bass response 
• Enhanced audio output efficiency 
• Minimize destructive wave interference 
• Help prevent front and rear wave cancellation 
• Easy installation with peel & stick application 
• Maximize performance for speaker installations 
• Sold in pairs