Lumishore EOS THX804 Color-Change Underwater Light & Driver

The THX804 is Lumishore's premium thru-hull underwater light, the largest fixture in the EOS Series. 12,000 verified fixture lumens is meaningful output. That's enough to create the broad halo effect around the boat that yacht owners specify when underwater lighting is a finished cosmetic feature rather than just a functional addition. The 110-degree ultra-wide beam angle is what spreads the light coverage. Narrow-beam underwater lights produce a tight bright spot directly below the boat. The THX804's wide beam spreads light across a much larger area for a softer, more atmospheric look that pairs well with the long sleek lines of a 50-foot-plus yacht.

The THX designation in the model name calls out the external driver configuration. Lumishore's EOS Series splits into TIX (internal driver, serviceable from inside the hull) and THX (external driver, slightly less expensive, requires haul-out for service). For a high-output fixture like the THX804 at 12,000 lumens, the external driver design is what keeps the fixture body compact enough to fit a standard 1-inch thru-hull. Internal-driver versions of comparable output would need a larger fixture housing. The trade-off is that any future driver maintenance requires the boat to be hauled, since the driver lives outside the hull on the back side of the fixture. For owners who keep the boat in a permanent slip and don't expect to need driver service for years, the THX configuration is the right balance of output and install simplicity.

Color control runs through Lumishore's EOS ecosystem. The light is fully color-changeable through 12 factory presets, infinite-color selection on the color wheel, color sweep (smooth fade through the spectrum), color scene (preset multi-color sequences), DMX control for theatrical-grade programming, and sound-to-music mode that pulses the lights with the boat's audio system. Control happens either through a compatible Lumishore-partner MFD on the marine network or through the optional Lumishore Display (a dedicated dash-mount controller). For yachts with an EOS i-Connect Hub already installed, the THX804 plugs into the existing system. For new installations, you specify the controller path based on whether you want chartplotter integration or a dedicated lighting control panel at the dash.

The fixture body uses Lumishore's standard 1-inch thru-hull fitting that matches the rest of the EOS Series, which means the install hole pattern is consistent if you're mixing fixture sizes on the same boat. Flush-fit design with extremely low profile minimizes drag and gives a clean external hull appearance. Suitable for transom, side-hull, or bottom mounting depending on the yacht's design aesthetic and the lighting effect you want. The LED engine is rated for over 50,000 hours of operation, which is the equivalent of running the lights nightly for over 10 years. The 3-year warranty on the fixture is one of the longer warranty periods in the marine underwater lighting market.

One install note. Thru-hull underwater light installs are haul-out jobs and benefit from being done by a marine electronics installer with underwater lighting experience. The hole through the hull, the bedding details (5200 is the typical adhesive), the cable routing through the hull skin, and the alignment of the fixture with the water flow at speed all need to be done correctly. For high-value yachts in particular, a bad install on a $4,000 fixture is the kind of thing that's worth paying a specialist installer to avoid. We can recommend an installer in your area and confirm the EOS control system pairing before you commit to the kit. The package includes the THX804 fixture, the external multi-channel driver, and the install documentation. Mounting hardware specific to your hull (backing plate, gaskets) may need separate specification.

One thing worth knowing about premium underwater lighting installations. The cost of the fixture itself is only part of the total install cost. The haul-out, the bedding work, the cable runs through the hull, the driver mounting, the control system integration, and the testing all add to the project cost on top of the fixture price. For a high-output fixture like the THX804, the typical total install cost (fixture, install labor, haul-out time) runs well above the fixture's purchase price. That math is normal for yacht-grade underwater lighting and worth budgeting accordingly. We can help you spec the total install scope and get realistic quotes from installers before you commit to the project.