Hella Optilux 357211011 LED Light Wiring Harness

Running a pair of LED lights or light bars off your boat's 12 volt system sounds simple, right up until you melt a dash switch or blow a fuse at the worst possible moment. This Hella Marine Optilux harness (part 357211011) is the clean, done-right way to wire two lights from a single switch. It's a complete kit. Relay, switch, weatherproof DT connector, and a 30 amp inline fuse all come in the box, so you're not sourcing parts from three different bins to finish the job.

Here's why a harness like this matters. High-wattage lights pull real current, and a typical dash toggle isn't built to carry it. Wire the lights straight to the switch and that switch becomes the hottest, weakest link in the circuit. It'll fail on you, usually the first cold night you actually need the lights. This harness puts a relay between your switch and your lamps. The switch only carries the small trigger current, and the heavy load runs on short, fused battery cable through the relay. That's how you get lights that come on every time and a switch that lasts.

Capacity is two lights at up to 150 watts each, 300 watts total, all on a 12 volt DC system. That covers a lot of real setups. A pair of spreader lights on a hardtop, fog and driving lamps on a center console, a couple of deck floods for night work, or dual light bars on a T-top. One switch, both lights, clean and simple.

The connector is a DT style Deutsch plug, which is the right call for a boat. Assembled correctly, it seals against spray and stays put in a chop. We still tell every customer the same thing: hit the pins with a little dielectric grease before you seat them, especially if you run in salt. Corrosion is what kills marine wiring, not the wire itself. A minute of prevention here saves you a flickering-light headache two seasons down the road.

Think about where the relay lives before you start pulling wire. You want it somewhere dry and cool. Under the console or up near the helm is ideal. Down by the bilge or bolted to a hot engine cover is asking for trouble. Keep your connections tight, use a proper crimp on the DT pins instead of just twisting them, and you'll have a circuit that behaves. Two 150 watt lights pull somewhere around 25 amps at 12 volts, so the included 30 amp fuse gives you a bit of headroom while still protecting the wiring if something shorts.

The included switch gives you one clean control point for both lights. No fumbling with two separate toggles, no guessing which one runs which lamp. Flip it and both come on together. For a lot of boaters that single-switch simplicity is the whole reason to run a proper harness instead of a rat's nest of butt connectors behind the dash.

Who's this for? Anyone adding a pair of auxiliary lights and wanting to do it once. It's ideal for Optilux LED lights and light bars, and it'll happily run any 12 volt light that stays inside the 150 watt per lamp limit. What's it not for? If you're hanging something bigger than 150 watts on each side, this isn't your harness. You'd want a heavier setup with a bigger fuse and thicker cable. But for the vast majority of dual-light installs on the water, this is exactly the piece that makes the job easy and keeps it reliable.

Hella Marine builds gear around a fit-and-forget idea, and this harness lives up to it. It's a straightforward part that does one job and does it well. Match it with a pair of quality LED lamps, take your time on the connections, and you've got auxiliary lighting you won't have to think about again. Set it up right the first time and spend your energy on the water, not under the console with a test light.