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Proline X Direct Fit Subwoofer Boxes

The Proline X Vehicle Specific Series is a line of direct-fit subwoofer enclosures engineered to install cleanly into specific vehicles without cutting, drilling, or permanent modification. Each enclosure is designed around the vehicle's factory interior dimensions, available cavity space, and mounting locations. Currently fits Ford F-150 (2015-2023, 2024-2025), F-250 (2017-2023), Ford Bronco, Ford Maverick, Toyota Tacoma (2015-2023), and Jeep JK (2007-2017 4-door). Available unloaded or pre-loaded with the driver. Lineup is expanding.

Tuning Frequency Vehicle Match
Material High-Density MDF
Power Rating Stealth Fit
Ideal For Truck & SUV
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Built Different. Built Better.

Every Proline X enclosure is manufactured in our Tullahoma, Tennessee facility using materials and construction methods that most enclosure brands don't touch.

Langboard Elite MDF

Langboard Elite MDF

48.5 lb/ft³ density and 200 psi internal bond strength, the highest-grade MDF available for enclosure construction.

1-Year Warranty

1-Year Warranty

Full coverage on materials and construction defects. We stand behind every enclosure we build.

Driver-Matched Tuning

Driver-Matched Tuning

Internal volume, port tuning, and cabinet dimensions are spec'd to each driver diameter, not a universal fit applied across sizes.

Made in Tullahoma, TN

Made in Tullahoma, TN

CNC-manufactured in our Tennessee facility on ShopSabre routers. Not imported. Not outsourced.

Direct Fit Subwoofer Boxes Built for Vehicle-Specific Installation

What "Vehicle Specific" Actually Means

A universal subwoofer enclosure is sized to a driver. A Vehicle Specific enclosure is sized to a vehicle. The difference matters because most factory cab interiors don't accommodate a generic enclosure cleanly. Behind-seat cavities have specific dimensions, hump heights, and panel angles. Cargo bay floors slope. Wheel wells eat into available width. A box that doesn't account for those constraints either won't physically fit, will block factory function (folding seats, cargo tie-downs, factory storage), or will require permanent modifications to install.

The Vehicle Specific Series is built to the vehicle first. We measure factory interior dimensions, mounting points, and unused cavity space. The enclosure is designed within those boundaries, with internal volume calculated to acoustically match a driver in the size class the install location supports. The result is an enclosure that drops into the vehicle, mounts to factory anchor points (or sits in factory cavities without modification), and produces clean bass from a location the vehicle was never designed to host one.

Vehicles We Currently Fit

Ford F-150 (2015-2023) and F-250 Super Duty (2017-2023): Behind-seat enclosures in single 10, dual 10, and Passive Radiator Edition variants. The behind-seat cavity in these trucks is the cleanest install location available, and our enclosures are built to occupy it without affecting seat travel or interior trim. The PR Edition adds a passive radiator for additional low-frequency extension in the same physical footprint.

Ford F-150 (2024-2025) and F-250 Super Duty (2024-2025): Behind-seat enclosures sized for the redesigned cab. Currently single 10 and 12 inch loaded options available. The 2024+ trucks have different behind-seat geometry than the 2015-2023 generation, so the enclosures are not interchangeable.

Ford Bronco: Dual 12 inch down-firing sealed enclosure. Built to fit the Bronco's cargo configuration with a down-firing baffle that fires into a flat surface for clean low-frequency loading.

Ford Maverick: 10 inch behind-seat enclosure with both standard and Passive Radiator Edition variants. The Maverick's compact cabin requires a low-profile design that the standard enclosure addresses; the PR Edition adds extension in the same footprint.

Toyota Tacoma (2015-2023): 10 inch behind-seat enclosure built for the third-generation Tacoma's cab dimensions.

Jeep JK (2007-2017, 4-door): 12 inch enclosure for the JK 4-door, sized to fit the Wrangler's available install location.

The lineup is expanding as additional vehicle fitments are tooled. If your vehicle isn't currently listed and you want a fitment, contact our tech team. Vehicle-specific enclosure development is one of the build paths we offer for serious projects.

Construction Adapts to Each Vehicle

Vehicle Specific Series enclosures use the construction method that best fits the vehicle's install location. Some vehicles call for traditional Dado and V-Groove panel construction (for boxes with conventional rectangular geometries that can be panel-built). Others, particularly tight behind-seat installs and irregular cavity fits, are built using stack fabrication (horizontally stacked CNC-cut MDF layers glued and clamped into a single solid block). The construction method is chosen by what the install location requires, not by what's easiest to manufacture.

All cabinets are built from Langboard Elite MDF (48.5 lb/ft³ density, 200 psi internal bond strength), the highest-grade MDF available for enclosure construction. Every enclosure is CNC-cut on ShopSabre routers in our Tullahoma, Tennessee facility.

Build Inclusions

The Vehicle Specific Series ships complete with polyfill (sized to the specific enclosure volume) and 12 gauge OFC pre-wiring landed at the Proline X composite terminal cup. The terminal cup is the Proline X ABS/carbon fiber composite cup, designed for clean wire termination at higher gauges than standard spring-clip cups will accept.

Driver mounting uses threaded inserts (or T-nuts depending on driver and enclosure) pre-positioned for the driver's bolt pattern. The cabinet exterior is finished in plush black carpet only. Plush black is the only finish available for the Vehicle Specific Series.

Loaded vs Unloaded Options

Several Vehicle Specific enclosures are available either as the enclosure alone or with the driver pre-installed. The loaded version arrives ready to mount in the vehicle, connect to the amplifier, and play. The unloaded version lets you supply your own driver (useful if you already own one or want a specific driver model). For Ford F-150 fitments specifically, loaded options include Kicker CompRT, JL Audio TW3, Audiomobile Evo, and Wavtech thinPRO drivers.

Frequently Asked Vehicle Specific Questions

What does "direct fit" mean?

The enclosure is designed to install in the vehicle without cutting panels, drilling holes, or making any permanent modifications. It mounts to factory anchor points or sits in factory cavities (typically behind-seat or cargo bay locations). The vehicle can be returned to fully stock condition if the enclosure is removed.

Will my factory seats still function with the enclosure installed?

Yes. Each enclosure is dimensioned to fit within the available behind-seat cavity without affecting seat travel, recline, fold-down function, or any other factory seating feature. For the F-150 and F-250 fitments specifically, this is a hard design constraint we test against during development.

What's a Passive Radiator (PR) Edition enclosure?

A passive radiator is an unpowered cone that's tuned by the air pressure inside the enclosure. It extends low-frequency response below what the active driver alone would produce, similar to what a port does in a ported enclosure but without the port noise or external dimension increase. PR Edition enclosures are the same physical size as the standard enclosure, with the passive radiator built into the cabinet wall. The result is more low-frequency extension in the exact same footprint.

Can I use a different driver than the loaded versions list?

Yes, if you buy the unloaded enclosure. The unloaded SKU is the bare enclosure built to vehicle dimensions, with internal volume calculated for a specific driver size class. You can install any driver in that size class that fits the cutout. The loaded versions exist for buyers who want a single-decision purchase with a known matched driver.

Is my vehicle on the list?

Currently we fit Ford F-150 (2015-2023, 2024-2025), F-250 Super Duty (2017-2023, 2024-2025), Ford Bronco, Ford Maverick, Toyota Tacoma (2015-2023), and Jeep JK (2007-2017 4-door). The lineup is expanding. If your vehicle isn't listed, contact our tech team. Custom vehicle-specific builds are one of the paths we offer for buyers willing to support the development cost.

How long does installation take?

For most Vehicle Specific enclosures, install time is 30 to 60 minutes including running power and signal wires from the amplifier. The enclosure itself drops into the install location in minutes. Most of the install time is wiring the amplifier, not mounting the box. Loaded versions are faster since the driver and terminal cup wiring are already done.