Partsam 15.5" LED Trailer Light Bar — 3-ID Red Marker & White Reverse, Slim Submersible

Partsam's 15-inch dual-function light bar combines the DOT-required 3 ID red marker lights with an 8-LED bright white reverse/load lamp in a slim, fully submersible housing.

Compact, rugged, and engineered for trailer, RV, and heavy-vehicle use, this Partsam light bar delivers two distinct lighting functions from a single low-profile unit. It meets FMVSS visibility needs for wide vehicles while offering a clear-lens white backup/load light to illuminate hitching, loading, and reversing tasks. Built with an ultra-thin waterproof body and hardwired three-conductor cabling, the lamp is suitable for horizontal, vertical, or angled mounting where space is limited.

How does this light bar meet legal marker requirements?

The unit provides three red identification marker lights spaced to comply with DOT expectations for vehicles wider than 80 inches. Its clear lens houses bright red LEDs that are visible across a wide angle, ensuring the vehicle’s width is clearly indicated at night and in poor weather. The slim design doesn’t sacrifice visibility while fitting narrow mounting locations.

• Three red ID LEDs integrated into a single 15.5" assembly
• Wide-angle illumination aligned with FMVSS/DOT guidelines
• Clear lens improves contrast and visibility
• Low-profile housing ideal for narrow mounting spaces

Can one light serve both marker and reverse lighting needs?

Yes — Partsam’s bar is a dual-function lamp with separate wiring to run red marker lighting or eight bright white LEDs for reverse or loading light. The three-wire hardwired setup lets you activate either function independently when connected to the proper circuits. This versatility reduces the number of fixtures needed on trailers, boats, and utility vehicles.

• White wire = ground; red + white for red marker lights
• Black + white for the 8 white reverse LEDs
• Independent circuits avoid interference between functions
• Ideal for backup illumination, night loading, and hitching

What are the physical dimensions and mounting requirements?

The lamp measures 15.5" long, 1.3" tall and 0.47" thick, with a 14.5" hole center-to-center for fastening. Surface mounting requires a roughly 0.57" circular cut-out per wiring pass; mounting screws are not included. Its ultra-low profile makes it suitable where clearance is limited or a streamlined look is preferred.

• Overall size: 15.5" x 1.3" x 0.47"
• Mount hole spacing: 14.5" center-to-center
• Required cut-out: ~0.57" diameter for wiring
• Mount horizontally, vertically, or at an angle

Is this light durable and waterproof enough for trailer use?

The Partsam bar is built as a submersible, waterproof fixture with corrosion-resistant components suitable for marine and roadside exposure. Its sealed housing protects LEDs and wiring from moisture, road spray, and harsh environments. The narrow profile still provides robust protection so it performs reliably on boats, trailers, and heavy equipment.

• Submersible waterproof construction for wet conditions
• Sealed clear lens to prevent water ingress
• Low-profile design resists accidental damage
• Long-lasting LED diodes reduce maintenance

Who is this for? This Partsam dual-function 15" light bar is aimed at trailer owners, RV and motorhome users, fleet managers, and anyone who needs DOT-compliant identification markers plus a compact reverse or load light. It's especially useful for vehicles with limited mounting space, boat trailers exposed to water, and work trucks that benefit from brighter, focused white illumination for night tasks. Installers and DIY enthusiasts will appreciate the simple three-wire hookup and flexible mounting orientation.