Lumens buy brightness. They do not buy distance.

Start with two lamps from our own range.

The TC-Q90C is 90W and makes 9,000 lumens. The TC-R100C is 100W and makes 9,000 lumens. Same output, near enough the same power. One puts its beam 450 metres down the track and the other 700.

That gap is 250 metres of stopping distance, and the lumen figure — the number almost every listing leads with — gives you no way to see it coming.

What each number actually measures

Lumens is total light leaving the lamp. All of it, in every direction the optics allow. It is a measure of how much, and it says nothing about where.

Beam distance is the distance at which the beam still puts one lux on the target. One lux is the industry convention, and it is roughly the level at which you can pick out an obstacle — not the level at which you can read a number plate. It is a measure of where.

A lamp that scatters 9,000 lumens across a wide arc and a lamp that focuses the same 9,000 lumens into a narrow one produce identical lumen figures and behave nothing alike at 90km/h.

The whole published set, in one table

Every model below has a detail page, and the figure comes from the same data that page prints. The rest of each range is listed on its category page.

Read down the beam column, then across to the lumens. They do not track each other.

Same power, same output, five times the reach

The clearest case is not the driving lights. It is three 40W work lights.

The TC-SS40 makes 6,000 lumens and reaches 400 metres. The TC-S18 makes 6,000 lumens. The TC-R12 makes 6,000 lumens. Their beam distances are 80 metres and 65 metres.

Same power draw. Same total output. One reaches five times further than another. Nothing about that is a quality difference — it is the optics doing what they were designed to do. The TC-SS40 concentrates the light; the other two spread it across the ground beside the vehicle, which is exactly what you want on a work light and exactly what you do not want on the highway.

Two more from the same table, both worth knowing:

• TC-S40 and TC-SS40 both reach 400 metres. The TC-SS40 makes 6,000 lumens and the TC-S40 makes 3,800. Same reach, more spill — the extra output is going sideways, lighting the verges rather than the vanishing point.
• TC-C20 and TC-T20W are both 20W making 2,000 lumens. They reach 250 and 350 metres.

So which number do you buy on

Work out what the light is for first.

Down the track, at speed. Beam distance is the number. You are buying the distance at which an obstacle stops being a shape and starts being a decision. The TC-R100C’s 700 metres is the longest reach in the table above — though not in the range, which is its own story below.

Around the vehicle, stopped. Lumens is the number, and beam distance is almost a negative — a spot beam at a campsite lights one tree brilliantly and leaves you working in its shadow. This is what the TC-S18 and TC-R12 are for.

Both, on one vehicle. That is what a combo pattern and a pair of lamps are for, and it is the usual answer for a build that drives at night and then camps at the end of it.

Whatever you fit, work out the current before you buy the switching for it. A 90W lamp is 7.5A at 12V, and a panel has a ceiling — see sizing a switch panel.

The longest beam in the range is on a lamp we cannot show you

The table above covers the models with a detail page. The rest of the range is listed on the category pages, and two of those listings beat everything in the table: the TC-W231R publishes 1,000 metres and the TC-W70W 820 metres. Three more sit level with the TC-R100C at 700.

So why is the 1,000-metre lamp not the hero of this article?

Because it has no product photography on file. A detail page whose main image is a placeholder converts worse than no detail page at all, so the rule here is that a model earns a page when there are usable shots of it — not when its numbers look good. The TC-W231R has the best beam figure we hold and no photograph, and the honest consequence is that it stays a line on a category page until that changes.

It is worth knowing about anyway. If 700 metres is not enough for what you drive, ask — the model exists, the figure is on file, and we would rather send you the specification by email than pretend the range stops at the models we have pictures of.

Watts are not the answer either

One more number to distrust, because it is the one people substitute when they have learned to distrust lumens.

The TC-4R40 is a 40W work light making 6,500 lumens and reaching 350 metres. The TC-W45 is 45W, makes 3,500 lumens — nearly half — and reaches 425 metres. Five more watts, half the output, seventy-five more metres of reach.

Wattage tells you what the lamp costs you in current, which matters when you are budgeting circuits on a switch panel. It does not tell you how much light comes out, and it certainly does not tell you where that light goes.

Where the figures stop

Some of our lamps have no beam distance published. The TC-R140 is one: 140W, 9,400 lumens, Osram emitters, 6500K, and the beam distance field is empty because the factory has not confirmed one.

That is deliberate, and it is the same rule everywhere on this site. A beam distance is a test result. Where we hold one, it is printed and you can hold us to it. Where we do not, the field stays blank rather than carrying a number somebody estimated from the wattage — which is exactly how a 40W pod ends up advertised at a kilometre.

The same applies to certification on these lines. Our switch panels hold CE, FCC, RoHS 2.0 and REACH with published certificate numbers. Our driving lights, work lights and light bars publish no marks at all, because we hold no certificates on file for them yet.

Where to start

If you know the distance you need, the table above is sorted for you. If you know the job instead — highway, tracks, camp, or all three — send us the vehicle and what you drive at night, and we will tell you which pattern fits.

The driving lights are the long-reach end of the range, and the work lights are the close-in end. Every model’s own figures are on its page.