The TriLite DGLED is a guide light set that marks where the dock opening is, so a driver backing a trailer can find it in a mirror instead of guessing. Each fixture carries 50 LEDs behind impact-resistant polycarbonate.
Two electrical versions exist. The DGLED-12/A runs on 12-24 volts, AC or DC, and the DGLED-120/A runs on 120 VAC. On the manufacturer's page, only the 120 VAC version is listed as UL/cUL listed, which is worth knowing if your specification requires it.
One thing these are not: stop and go signal lights. Guide lights mark the opening. The SG10, SG20 and SG30 families handle red and green communication between the dock and the driver. Different job, different product.

How do DGLED guide lights help a driver find the dock opening?

They mark the edges. A driver reversing a 53-foot trailer is working from mirrors, and in a dim bay or after dark the opening stops being obvious well before the trailer gets near it. A lit marker on each side gives a fixed reference the driver can line up against. Fifty LEDs per fixture is enough output to read at a distance, and the polycarbonate housing is there because things at dock height get hit.

Which DGLED electrical version do you need?

Match it to the supply you are wiring into. The DGLED-12/A covers 12 to 24 volts and accepts AC or DC, which suits a low-voltage circuit or a control panel already running at that level. The DGLED-120/A takes standard 120 VAC building power. One point to carry into your specification: the manufacturer page assigns UL/cUL listing to the 120 VAC units, and that statement should not be stretched to cover the low-voltage model without evidence.

Are DGLED guide lights the same as stop and go dock lights?

No, and ordering one when you need the other is a common mistake. Guide lights are passive markers. They show the driver where the opening is and they stay on. Stop and go lights are a communication system: a red and green signal that tells the driver whether it is safe to move, controlled from inside by the dock crew. The SG10, SG20 and SG30 families cover that. Plenty of docks run both, because they solve different problems.

What comes in a DGLED set?

This is the question to settle before you order. The product is sold as a set, and one competitor listing describes dock guide lights as a set of two, which matches how the fixtures are used, one per side of the opening. Supply Owl's own package contents have not been verified against the current workbook, so confirm the quantity, the lens color and whether any mounting hardware or controls are included rather than assuming the industry norm.

What should you check before installing?

Three things. The supply voltage, which decides the model. The mounting positions, which should put each fixture where a driver sees it in a mirror on the approach rather than where the conduit run is shortest. And the installation documentation, which TriLite publishes as a product information sheet alongside the product page. Mounting height and spacing make more difference to how well these work than anything in the specification.

What is confirmed and what still needs checking?

Confirmed from the manufacturer: 50 LEDs per fixture, impact-resistant polycarbonate housing, the two electrical versions, and UL/cUL listing on the 120 VAC units. Not yet confirmed: Supply Owl's exact SKUs, the original item description, set quantity, current retail price and whether the 120 VAC version is stocked at all. Those come from Joe's workbook, and the page should not carry a firm claim on any of them until it has been read.

Who orders dock guide lights?

Facility and warehouse managers fitting out a new dock, and maintenance leads replacing markers that have been knocked off or have failed. The common trigger is a near miss or a damaged dock seal, where a driver misjudged the approach. They also go in as part of a broader dock safety package alongside signal lights, dock lights and wheel restraints.