Review: Starrylight DXM (Tested Snorkeling)

I’m reviewing the Starrylight DXM, a budget diving light. It peaked my interest when I read a great review on BLF about it. I was going snorkeling in some months and really wanted to have a light with me to tactically strobe me some turtles. When TomTop offered to provide it for review, I was pretty happy to agree.

Buy the light here:
And a very special thanks to TomTop for the light!: Tomtop – Loving, Shopping, Sharing

Manufacturer Specs:

Product Model: DXM
Materials: Aircraft Aluminum
Light Color: White
Lumens: Max.850lms
Power Supply: 1 * 18650 Lithium Battery (with tube) / 1 * 26650 Lithium Battery (without tube)
Waterproof: IPX8
Diving Depth: max.50m
Item Size: 13.6 * 3.8 * 3.7cm / 5.4 * 1.5 * 1.5in(L * Head Dia. * Tail Dia.)
Item Weight: 200g / 7.1oz
Package Size: 15 * 7 * 6cm / 5.9 * 2.8 * 2.4in
Package Weight: 217g / 7.7oz



The DXM is a 26650 (or 18650 with the included sleeve) powered light designed specifically for diving. It has a cool-white XM-L2 emitter controlled by a magnetic sliding switch with an infinitely variable brightness that lets you go reeeeally low, really bright, or anywhere in between.


The light came wrapped in bubble wrap inside a plain white box.

Included were two very nice lanyards: A diving one, and a standard one. They’re honestly really good.

Also included was an 18650 sleeve.


The design is fairly simple and pretty enjoyable. It fits well in the hand and is super simple to use.

The head has some fins that I think are more decorative than anything. They do look nice. The light isn’t driven very hard, so I’m not worried about them being optimal.

The switch area has ovals machined around that help grip the light when unscrewing a ring right under the switch. When that ring is removed, you are able to slide out the magnetic switch to clean it. I was surprised at how much metal bits there were in the ocean. There were lots of bits of metal attracted to the switch after a day of snorkeling. It was easy to clean them out by removing the switch.

+Build Quality:_

Out of the box, as usual, there were no blemishes anywhere to be found. Reflector is clean, and there’s no fingerprints or smudges on the lens. The threads came lubed, but I added more just in case.


The anodizing took me by surprise. It is very well done, and very resistant. I’d say it’s as good as Nitecore’s. It has a sort of eggshell finish: not shiny, but not matte either. I love it. It held up great in the ocean. When I didn’t use the light, I’d have it dangling from my wrist and it must have scrapped hundreds of rocks. Sometimes it was just being dragged over rocks constantly. There is a very minimal amount of knicks, and only one scrape is kinda visible.


The tailcap has some machined grooves that help unscrew it from the body. The tailcap also has a huge cut out at the end for attaching lanyards. That cutout is also flat on the end, so tail standing is possible.

There’s no knurl anywhere on the light, but the machined ovals and grooves provided plenty of grip and made it easy to unscrew the tailcap and ring for the switch.

The magnetic switch slides up and down to increase and decrease brightness. It’s made out of a big chunk of plastic that’s super easy to find. The sliding action is smooth with the perfect amount of resistance to make sure it moves easily to the output you want it to be at, but won’t move accidentally. The switch came lubricated to provide the smooth action.

There are no sharp edges anywhere that matters on the light. There’s a bevel on every edge your hand slips on to. There is a sharp edge in the groove where the switch sits, and on the inside edge of the lanyard hole, but I only noticed them now that I’m looking closely. Not once when I used the light did I notice any of those edges since it’s pretty much impossible to accidentally touch them.

It has a lot of threads. It takes six full rotations to get the tailcap off. The threads are triangular but squared of at the ends, so trapezoidal? The threads are anodized. That means the light can be locked out which is important because the magnetic switch has parasitic drain.

The o-rings are a thing of beauty. There is two, and they’re thick. They really press against the tailcap such that there’s quite a bit of resistance when you’re screwing and unscrewing the tailcap. It gets a bit tiring, but it’s great for waterproofing the light.


The insides are accessible by removing the retaining ring from the front. Mine is all scratched up since I opened it a few times. It’s annoying to open since pliers slip and scratch the finish.

The reflector is smooth and clean.

The pill gets tightened into the head by a retaining ring, but without that ring it basically floats in there. The pill has no threads and is just smooth. Good thing it has that ring though. It still manages to get warm on the outside.

The lens and o-ring are massive! They’re both incredibly thick! It seals up very well. It was already really tight when I tried to tighten it more “just in case.”


The deepest I took the light must have been about 30 feet where I tied the lanyard to a rock and set it on the sand for about 40 minutes, then just resumed using it normally in the water. It was constantly in 7+ feet of water for hours most days for two weeks. There was absolutely no water ingress.

I can safely say that this light makes a perfect snorkeling light. I can’t say it’ll survive diving, only because I didn’t dive with it. I am certain it would survive. It has all the necessary seals and features to do so, Still, since I couldn’t test it myself I won’t know for sure.

If you buy this light with the intention of going into the water with it, make sure the lens retaining ring is tightened down, and generously lube the threads and o-ring. Also, look into the head and make sure that the o-ring is seated correctly just to be safe.


The big reflector makes it a somewhat throwy beam. The beam is clean of artifacts and the tint isn’t so blue. Beam profile is a pretty good mix of throw and flood. It’s cool white for sure, but not blue. I do wish it was available in a neutral color, as always. But it wasn’t an awful experience. It was easy enough to swap in a warmer tint.

I thought I wanted a floody light when I was snorkeling, but actually prefer the tighter beam to cut through the particles in the water.

I measured 15480cd or 249 meters of throw. The light is a bit underpowered. It was 2.1 amps on the highest mode, and with a spring bypass on the driver spring, 2.4 amps. Since it would essentially be water-cooled underwater, I think it’d handle a bit more heat. At least 2.8 amps would have been good. Even with the pill it has now.

Here’s a beamshot of the DXM lighting up a treeline that’s about 180 meters away:

User Interface:

The UI is pretty simple. Move the switch up until the desired brightness has been reached, move the switch back down to decrease brightness. There’s a bit of a dead zone which I wish was completely removed, but it’s not a deal breaker.

You can get this light incredibly low. Lower than the lowest mode on my H52. So low that your eyes have to be adapted to the dark to be able to see it in pitch black.

So far, I love the magnetic switch. I worked perfectly underwater and I haven’t had anything go wrong.

Again, the switch has parasitic drain. More so than other lights. When not in use (outside of water) lock out the tailcap. I’ve used it for days without locking it out and the battery had lasted, but it’s still good to be careful. When you lock it out, the tailcap is still completely over the o-rings, so if you accidentally dive into the water that way it wont mess up. But still, just to be safe, tighten the tailcap.


  • Very waterproof.
  • Affordable.
  • Great build quality.
  • Long runtime with 26650.
  • Magnetic switch.
  • Decent brightness


* Of course, could definitely be brighter.

* Extra o-rings would have been nice.

* Parasitic drain (a nature of the switch).

Final Remarks:

This is a great snorkeling light. It might be a great diving light too. It’s so easy to use that I could gift it to my grandpa and be sure he’d know how to work it. It’s a bit underpowered, but ~700+ lumens is still pretty darn bright for those who haven’t seen a modern light. It worked beautifully underwater and made snorkeling even funner. It’s has a cheap price, but not cheap quality.

Extra Notes:

  • I’ve read from a user on BLF from the other review thread that if the emitters don’t have a similar Vf to the stock emitter, it could behave differently. Read that excellent review here: Review: Starry Light DXM.
  • My longest batteries fit.
  • I wrapped tape around the batteries and sleeves to minimize rattle.
  • I had MANY more underwater shots to show, but I just can’t find them. Sorry everyone.
  • There’s a user that received the same light (different branding) without thermal paste.

View all images and some extra images:

Thanks for reading! :slight_smile:

Pardon my pedanticism, but it’s piqued, not peaked.

Cool review!
What great pics, thanks.

Hi jescereal. Please, can you comment on the pill a little more? A couple weeks ago I received the solarstorm Dx1 flashlight which is the original ‘brand’ of this particularly shaped light. The star did not have thermal grease underneath it and the pill had about a millimeter space between it and the inner walls of the light. I’d like to know if the design has been improved with the name change. One obvious difference is that the solarstorm did not have anywhere as much lube on the threads/’O’rings as the starylight.

Thanks :slight_smile:


So dumb that dive lights aren’t overdriven…even dumber when they are underdriven

Great review in the elements it was designed for!

I think this light, with the recommendation of locking it out in storage, is the best general purpose light out there tight now.

1. Stupid tough and waterproof, really waterproof even locked out.

2. Super simple UI with multiple levels, anyone can use from 2 to 102 years old.

3. Battery selection of 26650,18650 or even 3x AAA if needed.

4. Moderate level of output with great runtime on 26650, no real heat issues

5. Around $20.

The negatives are some very fast PWM on lower settings (tolerable to me, and I do not like visible PWM) and having to lock out the light during storage due to parasitic drain in standby. But with this switch design, I would lock it out as the slide can come on if bumped forward, no matter the standby drain. I calculated the standby would drain a 4000ma battery in about 30 days, so no issues for a week of camping or whatever…

The light is emitter swappable, but I think a XM-L2 is the best choice, the Nichia 219B-V1 4000K I tried just kept the light on, I think the emitter Vf has to be close to the XM-L2 due to the driver design. A 5C and a 7A XM-L2 are in my lights now with no issues, and they are both great “car lights” locked out in the glove box.

Sure thing! It’s actually exactly as you describe! Pill has a gap around it. It’s why I called it a floating pill. Vey unfortunate, but at least it isn’t driven hard enough to affect it. When I added a spring bypass, it started getting warmer, which is good. But it could definitely be better. The fact that you can screw the retaining ring and press the pill tighter helps. It went from 4000 to 3870 lux in 30 seconds, then stabilized in the 3865-3870 lux area for a couple of minutes. Thats a 3.25% drop. In comparison, the X5R (also driven ay 2.1 amps) which has an integrated shelf went from 2900 to 2820 lux in 30 seconds, a 2.76% drop. It’s not too off. If it was driven harder, it absolutely would be a problem.

It did have a blob paste under the star. Not neatly, but it was there. I have another, so I’ll open it up to see if it’s consistent.

I agree on all your points! It is a pretty freaking solid light. Already planning on gifting mine to my grandpa since it’s so dead simple to use, and still much brighter than the gas station lights he uses. If he forgets it out where his goats are and it gets rained on, it’ll still work. Nice peace of mind.