Acebeam has a hot new little headlamp out! It’s a High CRI model, and can work with AA sized cells. Acebeam makes good stuff; read on to find out if this headlamp is too!

Official Specs and Features

Here’s a link to the official product page.

Versions

Just one body is available, but that body can be had in two emitter choices. They are CREE XPL HD 6500K or Luminus SST-20 4000K CRI 95+ LED (which I have here.)

Price

This light has a MSRP of $34.90. That’s a very compelling price for all that this light offers! Buy it at killzoneflashlights.com!!

Short Review

This is a neat little light. I like in particular that it’s available with 95+ CRI. Also useful is support for all AA sized cells, including NiMH and Li-Ion (14500).

Long Review

The Big Table

NiMH:

14500:

Standard measurement disclaimer: I am an amateur flashlight reviewer. I don’t have $10,000 or even $1,000 worth of testing equipment. I test output and such in PVC tubes!! Please consider claims within 10% of what I measure to be perfectly reasonable (accurate, even).

What’s Included

Acebeam H40 Headlamp

Headband

Spare o-rings (2)

Manual and paperwork

Package and Manual

Acebeam ships this light in a display ready slip fit box. Inside the box is some foam, holding the pieces very carefully. The back of the box is very informative, including output and runtimes for both emitters and 3 supported cell types.

The manual is good. It includes the UI, and also all of the info from the back of the box, and warranty info, etc.

Build Quality and Disassembly

This is a tiny little headlamp! There are a lot of ridges on the body, including some cooling fins directly behind the emitter.

One end of the light is thread locked closed. The other is labeled Open/Close and that’s the end with knurling, to assist with accessing the cell area.

The tailcap has a thick removable spring. The head has only a brass button, and to be honest, looks like either a frown or smiley face, depending on how you see it. There is no magnet in the tail.

The threads are well lubed, square cut, and anodized. Thus it’s possible to lock the light out with just a very small twist of the tailcap.

Even though this bezel looks removable, it’s at best, difficult to remove. I didn’t use any tools, but I wasn’t able to just twist it off. (Other users have done this successfully.)

Inside the cell tube is a little sticker indicating cell orientation. The head goes in first, as seen in the photo to the right.

Size

Officially the dimensions are: 64.7 mm long, 23.4mm in diameter, and the weight is 34g.

Sorry for the out of focus shot, but here’s the H40 with my force patina ReyLight Brass Pineapple.

And with the standard Convoy S2+.

Retention and Carry

This light has essentially only one carry mode, and that’s with the headlamp. The light slips in to two silicone loops, and fits very snugly. It’s possible to rotate the light inside this housing.

The light can be oriented with the button on top or bottom.

The headband has a silicone grip section all the way around the inside of the band, and stays in place very nicely. Also worth mentioning is that the silicone part that contacts the forehead is quite comfortable.

I’d love for there to be a magnet in the tailcap of this light. I do believe that’s a bit of an omission, but I also get it – this is a very dedicated headlamp.

Power and Runtime

The H40 is capable to run from many AA sized cells. This includes primary alkalines, NiMH, and 14500. It’ll even work properly with flat or button top cells, too.

Again, be sure to put the cell into the light positive end first.

Here are a number of runtimes.

Noteworthy about every test I ran is that the light does have LVP, and that includes for Li-ion and NiMH independently. Also when the cell voltage gets low, the light will flicker on and off to warn the user!

Turbo output with a NiMH cell isn’t quite like the Turbo of a Li-ion. It’s a much more subdued output, and fortunately the H40 is able to maintain that for quite some time.

High is marginally lower, but also very stable.

User Interface and Operation

There’s just one button on the H40. It’s a big orange square e-switch, and is in the center of the body. It can be on the top or bottom when the light is in the headband, per your preference. To be perfectly honest, the switch is probably my single least favorite thing about this great little light. It’s quite mashy. Double clicking for turbo is a bit difficult to do reliably. The switch works right, mind you, it’s just the actuation point is a bit under so much mashing that it’s … unusual.

Here’s a UI table!

State Action Result Off Hold Ultra-Low Off Click On (Mode memory, except Ultra-Low and Turbo) On Click Off Any (Non Turbo) Double Click Turbo Turbo Double Click Previous mode Any Triple Click SOS On Hold Ramp up to High (signified by three flashes) then ramp down to Low (signified by two flashes) Off Hold >3s Lock (signified by 3 flashes) Locked Hold >3s Unlock to On

Modes and Currents

Mode Mode Claimed Output (lm) Claimed Runtime Measured Lumens Tailcap Amps Turbo (14500) 600/220 1m/40m 602 1.98 High (14500) 150 65m 136 0.32 Low (14500) 20 7h 20 0.01 Ultra-Low (14500) 5 17h ~ ~ Turbo (NiMH) 180 80m 165 0.93 High (NiMH) 150 85m 114 0.69 Low (NiMH) 20 16h 15 0.02 Ultra-Low (NiMH) 5 43h ~ 0.02

LED and Beam

The light I have is the Luminus SST-20 4000K CRI 95+ option. The other is a Cree XP-L HD. The Cree has much more output (over 1000 lumens on Turbo) but the Luminus boasts >95 CRI. High CRI and headlamp seem to go together extremely well.

The reflector is small, of course. It has an orange peel texture. The small size of the emitter coupled with this reflector give a surprisingly tight hotspot, but there’s reasonable spill, too. This light will likely be good for hiking, and on-trail activities.

AA (NiMH)

14500 (Li-Ion)

Tint vs BLF-348 (KillzoneFlashlights.com 219b version) (affiliate link)

I compare everything to the KillzoneFlashlights.com 219b BLF-348, because it’s inexpensive and has the best tint!

Random Comparisons and Competitive Options….

Here’s a link to a relevantly filtered page on parametrek.com. I use that site a lot! There are some comparable lights. Most notably, many of the Zebralight headlamps. As far as I can tell, the H40 is the only option that supports all these cell chemistry options, which makes it truly stand out.

Conclusion

What I like

Very high CRI!

Warm emitter – 4000K claim, feels warmer

Nice tight hotspot, good for hiking

Multi-chemistry support

What I don’t like

Button is too mashy for my usage

No magnet

Up Next

Notes

This light was provided by killzoneflashlights.com for review. I was not paid to write this review.

This content originally appeared at zeroair.org. Please visit there for the best experience!

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