XTC 4" Speaker Baffles
Crutchfield Customer Review (What's this?)
Perfect way to isolate your speaker for better sound transmission. Removed the factory insulation that surrounded the stock speakers and installed this with new speakers. I think this is one of those "must haves" when installing new speakers. Protects from environment ( doors ) and helps small speakers perform at a better level.
Pros: Easy install.
Cons: nothing major - trim to fit the top flat part to clear factory speaker grill.