Overview

The Hella Marine 357211001 is a single-light wiring harness kit for switching and powering one auxiliary LED light or light bar from a 12 V system. It is rated for lights up to 300 W at 12 V and uses a relay so the helm switch is only handling control current, not full lamp load.

This kit is a straightforward way to clean up an install for a spreader light, cockpit flood, utility light on a hardtop, or a forward-facing light bar, especially when you want one switch to control one light. The harness includes a 30 A fused feed, a 12 V relay, and a 6 ft switch lead to reach a dash or helm panel.

Key features

• Single-light harness for one auxiliary LED light or light bar on a 12 V electrical system
• Supports lights up to 300 W at 12 V
• Includes a 12 V relay to keep high current out of the dash switch wiring
• 30 A fused power feed for circuit protection
• 6 ft (195 cm) cable with switch and a 1.5 ft (45 cm) fused lead for flexible routing
• Harness uses an ATP connector at the light end

What’s included

• Wiring harness with ATP connector and 30 A fuse
• 12 V relay
• Switch with 6 ft (195 cm) lead
• 1.5 ft (45 cm) fused lead
• Mounting instructions

Installation and setup

Mount the relay and fused feed where they stay protected from spray and standing water, then route the harness to the light while keeping the run supported and away from sharp edges. On boats, take the extra minute to secure the loom so it cannot chafe with vibration, and leave a drip loop before any connection points.

The switch lead is long enough for most helm or console installs. If you are running through bulkheads or a hardtop, use proper chafe protection and seal penetrations. For any splices or terminations, use marine-grade crimp terminals with heat-shrink to keep corrosion from creeping into the strands.

Compatibility and fit

This harness is intended for Hella ValueFit lights and light bars and can also be used with other 12 V auxiliary lights as long as the load stays within the 300 W rating and the connection at the light end is compatible with the ATP-style connector or is adapted correctly. Before ordering, confirm your light’s input leads, connector style, and that your planned mounting location is within reach of the harness routing.

Use on board

This is a good match for boat owners adding one auxiliary light with clean switching, such as a cockpit work light for night rigging, a hardtop flood for the deck, or a docking light that you want on a dedicated switch. It is also useful when you want the heavy current path kept close to the power source while the helm wiring stays lighter and easier to manage.