Attwood Marine LightArmor HP Series Underwater LED Light, 4 in, 800 lm, Surface Mount, 3 LED, SS316 Cover

Overview

The Attwood Marine LightArmor High Performance (HP) 4.0 is a 4 inch, 3 LED surface-mount underwater light for 12V and 24V DC boat systems. It is made for below-waterline installation and is available in Sapphire Blue, Tactical Green, and Intense White, with each color rated at 800 fixture lumens.

This compact LightArmor model works well on transoms, lower hull areas, and stern lighting layouts where a low outside profile matters. The 4.0 HP housing measures 4.00" long by 2.15" wide, with a .56" installed height, so it can add underwater lighting without the bulk of a larger fixture.

The light uses fully sealed waterproof electronics, reverse polarity protection, a heat sink cooling system with active overheat protection, and a lens made to resist impact. It is also resistant to corrosion, chemicals, and UV damage, which matters on boats exposed to saltwater, washdowns, sunlight, and vibration.

Key features

• 4.0 HP format with 4.00" length, 2.15" width, 3 LED layout, and .56" installed height for a low-profile underwater installation.
• 800 fixture lumens across the Sapphire Blue, Tactical Green, and Intense White color options.
• Compatible with 12V and 24V DC systems, with current draw varying by selected color.
• Heat-Sync cooling system with active overheat protection for submerged operation.
• Fully sealed waterproof electronics and reverse polarity protection for a cleaner installation process.
• Lens resists impact, while the housing is resistant to corrosion, chemicals, and UV damage.
• Aftermarket packaged part includes an electro-polished 316 stainless steel cover.
• 3 ft sheathed wire and minimal mounting hardware requirements help simplify routing and installation.
• CE certified for marine electrical use.

Variants

This LightArmor HP 4.0 underwater light is offered in three color configurations. Each version uses the same 4 inch, 3 LED surface-mount format and the same 800 fixture-lumen rating.

The main differences are the LED color and current draw. The dimensions, 12V and 24V DC compatibility, sealed electronics, reverse polarity protection, low-profile body, and 316 stainless steel cover in aftermarket packaging remain consistent across these variants.

• 65UW03B-7: Sapphire Blue. This option gives a blue underwater accent around the transom or lower hull, with 0.32 A draw at 13.6V and 0.16 A at 24V.
• 65UW03G-7: Tactical Green. This option gives a green underwater glow that suits fishing setups and night use around the stern, with 0.36 A draw at 13.6V and 0.18 A at 24V.
• 65UW03W-7: Intense White. This option gives a white light appearance for general underwater visibility, with 0.64 A draw at 13.6V and 0.32 A at 24V.

Installation and fit

This is a surface-mount underwater light, so it suits transom and hull locations where a low outside profile is preferred. The 4.0 HP model has 3.25" between mounting holes, a .56" wiring hole, .56" installed product height, and .30" wire collar depth.

All LightArmor underwater lights must be mounted below the waterline and operate only underwater. Plan the cable route and sealing points before drilling, and confirm that the mounting area is flat enough for the light body and cover to sit cleanly.

Electrical and operation

The light accepts both 12V and 24V DC boat power, which makes it useful on small center consoles, trailer boats, cruisers, and larger vessels with 24V banks. Current draw depends on the selected color, so the branch circuit, fuse, and switch capacity should be sized for the chosen variant and for the total number of lights on the circuit.

Reverse polarity protection helps protect the electronics during installation. The active overheat protection and heat sink cooling system matter because this unit is intended to run submerged, where the water around the body helps manage heat.

Use on board

The compact 3 LED format is a practical fit for transoms, swim platforms, lower hull accents, and small to medium boats where the owner wants underwater light without a large fixture. The color options cover accent lighting, fishing visibility, and clean white output for checking water around the stern at night.