Down4Sound Quad 18" Custom Kerf Ported Subwoofer Box (HAND MADE IN THE USA)

Description 0 Reviews Description *****Sales are final***** CURRENTLY Custom built Sub woofer Box, Each box is built to your exact wants and needs. Pictures are just examples of what we have built for customers in the past. (HAND MADE IN THE USA) **Maximum available dimensions for sub box to fit inside of. Its mandatory to provide and very important for you to measure so when you place your order you know your subwoofer box will fit in the space you have for it, there is no returns on these boxes as they are built to order to fit your exact needs** View All Close 0 Reviews View All Close

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Down 4 Soundcom

Updated 4/18/2026

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Frequently Asked Questions

What is the Down4Sound Quad 18" Custom Kerf Ported Subwoofer Box (HAND MADE IN THE USA)?

The Down4Sound Quad 18" Custom Kerf Ported Subwoofer Box (HAND MADE IN THE USA) is a car audio equipment made by Down4Sound. View full specifications and where to buy on this page.

Where can I buy the Down4Sound Quad 18" Custom Kerf Ported Subwoofer Box (HAND MADE IN THE USA)?

You can purchase the Down4Sound Quad 18" Custom Kerf Ported Subwoofer Box (HAND MADE IN THE USA) from authorized dealers listed in the "Where to Buy" section on this page. We recommend buying from authorized retailers to ensure warranty coverage and genuine products.