NITECORE NU25 MCT UL Review: The Lamp You Forget You Are Wearing

The verdict

We have not worn this lamp. What follows is a reading of what NITECORE publishes, which on this model is more interesting than usual because one of the specifications is genuinely unusual rather than merely competitive.

The published specification

Forty-seven grams is the whole argument

Weight on a headlamp is not carried, it is worn, and it is worn on the front of your skull where it acts on a lever arm. That is why a heavy lamp needs a tighter band to stop it sliding, why the tighter band is what gives you the headache, and why the lamp that gives you a headache is the one left in the drawer.

Forty-seven grams is the figure that makes this lamp interesting, and it is worth putting next to its rivals: the Petzl ACTIK CORE is 88 grams, Black Diamond's Spot 400-R is 86, and the Storm 500-R is 120. The NU25 is roughly half of the first two and well under half of the third, and crucially NITECORE quotes the figure *including* the bracket and headband, which not every brand does.

On a site that ranks by dividing published numbers, this is the attribute that most resists that treatment and most decides whether a lamp gets used. We score it accordingly.

The three color temperatures are the second reason

NITECORE publishes 3,000K, 4,500K and 6,500K on this lamp. That is unusual enough to be worth explaining, because most headlamps ship a single cool-white emitter around 6,500K for the simple reason that cool white produces the most lumens per watt.

Cool white is also the least comfortable choice for anything close and pale. Reading in a tent at 6,500K bleaches the page; 3,000K does not. Of the four lamps we have compared in this class, the NU25 is the only one whose manufacturer publishes a color temperature at all, let alone three of them, and for a lamp that will be used inside a tent as much as on a trail that is a more useful specification than the extra hundred lumens a rival offers.

The auxiliary red matters for the same reason. Red at very low output preserves dark adaptation and is far less likely to wake someone sleeping beside you, and having it as a separate emitter rather than a mode you cycle white through is the better arrangement.

#	Light	Max output	Battery	Lumens / $	Price
1	NITECORE NU25 MCT UL Lightest headlamp with a real published runtime	400	Sealed	11	$36.95 on Amazon→ Price as of September 27, 2026 — 11 lumens per dollar. #ad How we earn
2	Petzl ACTIK CORE Best hybrid: rechargeable or AAA cells	625	Replaceable	8	$77.70 on Amazon→ Price as of September 27, 2026 — 8 lumens per dollar. #ad How we earn
3	Black Diamond Spot 400-R Most complete published runtime table	400	Sealed	7	$59.88 on Amazon→ Price as of September 27, 2026 — 7 lumens per dollar. #ad How we earn

Prices pulled September 27, 2026. Lumens per dollar is the manufacturer's published maximum output divided by that price, recomputed every time the price moves.

1. Lightest headlamp with a real published runtime

NITECORE NU25 MCT UL

Lumens per dollar

11

Forty-seven grams including the headband, 400 lumens, and 45 hours at its 6-lumen setting. On a headlamp the weight figure matters more than the lumen figure, because the lamp you stop wearing produces no light at all.

Max output

400 lm

Runtime

45 h at 6 lm

Battery

Sealed

Water rating

IP66

What it gets right

• Forty-seven grams with the band on — you forget it is there
• Three color temperatures plus red, which is unusual at any price
• IP66 and a published 45-hour low-mode runtime

What it gets wrong

• Sealed 700 mAh cell; no way to carry a spare
• Four hundred lumens is modest for trail running at speed
• Flat band with no over-the-top strap on the ultralight version

Published specification

• Maximum output: 400 lumens — NITECORE published specification
• Beam distance: 132 m — NITECORE published specification
• Runtime: Up to 45 hours at 6 lumens — NITECORE published specification
• Battery: Built-in 700 mAh Li-ion, USB-C — NITECORE published specification
• Weight: 47 g (1.66 oz) including bracket and headband — NITECORE published specification
• Water rating: IP66 — NITECORE published specification
• Color temperatures: 3,000K / 4,500K / 6,500K plus auxiliary red — NITECORE published specification

Skip this one if

you need to swap a battery mid-shift. A sealed 700 mAh cell means your night ends when it does.

Buy it if: hikers, campers and anyone whose complaint about headlamps is that they bounce.

• Output 6.5
• Battery 4.5
• Weight 9.5
• Usability 8.5
• Overall 7.8

$36.95 on Amazon→

Price as of September 27, 2026 — 11 lumens per dollar. #ad How we earn

2. Best hybrid: rechargeable or AAA cells

Petzl ACTIK CORE

Lumens per dollar

8

Six hundred and twenty-five lumens stated to ANSI/PLATO FL1, 88 grams, and — the part that matters — it runs on the CORE rechargeable pack or on three AAA cells when the pack is flat. That is the answer to the sealed-battery problem, from the only brand here that bothered.

Max output

625 lm

Runtime

Published per mode by Petzl

Battery

Replaceable cell

Water rating

IPX4

What it gets right

• Explicitly states ANSI/PLATO FL1 conformity, which most brands here do not
• Hybrid power: the pack for daily use, AAA cells as the fallback that never fails
• Petzl publishes the CORE pack's cycle rating, so its service life is a stated number

What it gets wrong

• IPX4 — weather resistant, not submersible
• Eighty-eight grams is not ultralight
• The CORE pack is a Petzl part rather than a standard cell

Published specification

• Maximum output: 625 lumens (ANSI/PLATO FL1) — Petzl published specification
• Weight: 88 g — Petzl published specification
• Battery: CORE rechargeable 1,250 mAh / 3.6 V / 4.5 Wh, or 3 x AAA — Petzl published specification
• Battery compatibility: Alkaline, lithium or Ni-MH — Petzl published specification
• Water rating: IPX4, weather resistant — Petzl published specification
• Warranty: Lamp 5 years; CORE battery 2 years or 300 cycles — Petzl published specification
• Lighting levels: MAX BURN TIME, STANDARD, MAX POWER, plus red — Petzl published specification

Skip this one if

you want a submersible headlamp. IPX4 covers rain and nothing beyond it.

Buy it if: anyone whose headlamp has to work at the end of a long trip, when charging is not an option.

• Output 7.5
• Battery 9.0
• Weight 7.0
• Usability 8.5
• Overall 8.3

$77.70 on Amazon→

Price as of September 27, 2026 — 8 lumens per dollar. #ad How we earn

3. Most complete published runtime table

Black Diamond Spot 400-R

Lumens per dollar

7

Four hundred lumens for four hours, 200 for eight, 6 for two hundred and twenty-five. Black Diamond publishes lumens, runtime and beam distance for all three modes, and IP67 on top. There is nothing to guess at here.

Max output

400 lm

Runtime

4 h

Battery

Sealed

Water rating

IP67

What it gets right

• Lumens, runtime and distance published for every mode
• Two hundred and twenty-five hours on low is a genuine emergency reserve
• IP67 and a battery meter that shows an actual percentage

What it gets wrong

• Micro-USB in a year when everything else is USB-C
• Integrated battery — no spare, no re-cell
• Eighty-six grams is heavy next to the ultralight class

Published specification

• High: 400 lumens, 4 hours, 100 m — Black Diamond published specification
• Medium: 200 lumens, 8 hours, 60 m — Black Diamond published specification
• Low: 6 lumens, 225 hours, 12 m — Black Diamond published specification
• Battery: Integrated 1,500 mAh Li-ion, micro-USB — Black Diamond published specification
• Water rating: IP67, tested to 1.0 m for 30 minutes — Black Diamond published specification
• Weight: 86 g — Black Diamond published specification

Skip this one if

you have standardized on USB-C. Carrying a second cable for one device is a small annoyance that compounds on a long trip.

Buy it if: camp, dog walks and anyone who wants a headlamp whose numbers are all on the box.

• Output 6.5
• Battery 5.5
• Weight 7.0
• Usability 9.0
• Overall 7.7

$59.88 on Amazon→

Price as of September 27, 2026 — 7 lumens per dollar. #ad How we earn

Where it is weak

The sealed 700 mAh cell is the real limitation and it is not a small one. You cannot carry a spare, so the lamp's usable night is whatever that cell holds, and when the cell reaches the end of its cycle life the lamp is finished rather than re-cellable. Petzl's ACTIK CORE answers exactly this by taking three AAA cells when its pack is flat, and on a multi-day trip that difference is the whole ballgame.

Four hundred lumens is modest. For camp, reading, dog walks and ordinary hiking it is plenty; for trail running at speed or for picking a line down technical ground it is not, and the Fenix and Black Diamond lamps we cover go considerably brighter.

NITECORE also publishes only a maximum runtime — 45 hours at 6 lumens — and nothing for the modes in between. That is the same criticism we make of Olight and Fenix, and it is fair here too: you are told what the lamp does at its dimmest and left to guess what it does at the setting you will actually select. Black Diamond and Petzl both publish full tables.

And the ultralight version uses a flat band with no over-the-top strap, which is part of how it reaches 47 grams and is a fair trade rather than an oversight — but it is a reason it is not the lamp for running.

What IP66 covers, and what it does not

NITECORE publishes IP66, and the two digits mean different things worth separating. The first, 6, is the solids rating and it is the top of that scale: dust-tight. The second, 6, is the water rating and it covers powerful water jets from any direction.

What it does not cover is immersion. IP66 is a spray and jet rating, not a submersion one, so a lamp rated IP66 is fine in heavy rain and not rated for being dropped in a stream. Black Diamond publishes IP67 on both lamps we cover, where the 7 does mean immersion to a meter for thirty minutes, and that is a genuine advantage over the NU25 for anything near water.

For most uses IP66 is the more than adequate rating and the distinction never comes up. It is worth knowing which half of it you are relying on.

The MCT in the name is the specification

The model name is doing more work than model names usually do. MCT stands for the multiple color temperatures, and UL for the ultralight build — which is to say the two things that make the lamp worth buying are both named in it, and neither is the lumen figure.

That is a reasonable way to read the whole product. NITECORE has a large range that reaches far higher outputs than 400 lumens, so this lamp is not an attempt at a bright headlamp that fell short. It is a deliberate ultralight with an unusual emitter set, and it should be judged on whether those two choices are the ones you want.

Who should buy it

• Anyone whose complaint about headlamps is that they bounce, press or ache. This is the lightest lamp we cover and the figure includes the band.
• Campers and tent readers, for the 3,000K option and the auxiliary red.
• Hikers on day trips or overnights within reach of a charger.
• Anyone who wants IP66 and a published 45-hour reserve in a lamp this size.

Who should not

• Anyone going multiple days from power. A sealed 700 mAh cell has no answer to that; the Petzl ACTIK CORE does.
• Trail runners at pace, who want more than 400 lumens and an over-the-top strap.
• Anyone who needs a runtime figure for the mode they will actually use, which NITECORE does not publish.

What we cannot tell you

We have not worn this lamp, run its cell down, or been rained on in it. We cannot tell you whether the flat band slips, how the tilt bracket holds after a season, whether the 3,000K mode is as pleasant in practice as it reads on paper, or whether the lamp flickers at its lowest setting — no manufacturer publishes a flicker figure and we have no instrument to measure one. Every number above is NITECORE's own.