Upgrade the sound system in your BMW E46 with this custom-designed speaker adapter, allowing you to install Kicker 5 1/4" speakers in the front door of your BMW E46. The OEM speakers are 6 1/2", but this adapter makes it easy to replace them with 5 1/4" Kickers, offering improved sound quality while keeping the installation looking OEM. Key Features: Custom-designed for BMW E46: Specifically made for BMW E46 front doors, including the 325Ci (coupe). Compatible with Kicker 5 1/4" speakers: Allows easy installation of Kicker speakers that are smaller than the OEM 6 1/2" size. OEM-like installation: The adapter ensures the installation looks factory-installed, maintaining the car's original aesthetic. Vibration reduction: Recommended to use foam adhesive tape around the edges to seal and reduce any vibrations during use. Simple and efficient: Designed for a plug-and-play installation with no need for additional modifications. This speaker adapter is perfect for those who want to upgrade their BMW E46?s sound system with Kicker speakers without compromising the car?s interior look.