I'm looking for a decent Zoomie that will take a 20mm driver

Any thoughts on a decent Zoomie that will take a 20mm driver. It seems like any worth anything only take a 17mm.

I would like to get a light for 18650’s and 26650’s.

The Unique fire have decent quality but ugly lights, which is ok but there drivers are 17mm and not enough room to take it to 20mm.

I have a Ultrafire Z6 18650 that will let me mod from 17mm to 20mm. I ordered a glass lense and it will be good to go when done.

Any thoughts are appreciated.


Well, these might fall short of what you consider decent, but they take 20mm drivers. I’ve listed two versions in the OP of this thread: Mod: Zoomie with MT-G2

Edit: Just noticed banggood link is dead. Oh well, these lights are sold under different names here and there with small differences. Switches are not the best of quality.

SK98s take 20mm drivers and 18650s, but chances are have “hollow pills” (just a ledge vs solid shelf).

Still, as Barkuti will likely jump in, they can still be pushed fairly hard.

As long as they still have room for the thickness of the driver after I solder some copper(penny) under behind the LED.

Zeusray? zeusray - Google Search


Page says “backordered” but that’s been true off and on for a few years, they probably produce a few at a time.
Decently easy to mod. I’ve bought half a dozen of them or so over the last few years.

You can just fill the hole with some JBWeld and it’ll still provide a better thermal path than just air. Add Cu shavings for even better thermal properties.

“Lap” it flat when done so it makes good contact with the mcpcb, and use enough thermal ook like AS5 to fill any air-gaps, and you’re good to go.

Just adding a penny behind the pcb gives it more thermal mass, but not necessarily better thermal properties from pcb to the outside world. All the heat still would have to go from the edge of the penny to the shelf anyway; that’s the bottleneck.

With the ok 26650 Zoomie I’m dealing with, it has a hollow 20mm pill that a penny fits into perfect. I can stack about 10 before it would get in the way of the driver.

Pennies pre 82’?

Pennies pre-1982.
You can build a sorter/separator with a strong magnet and an inclined plane:

Supfire F3-L2

still one of my favorite zoomie

There are some nice, affordable fully regulated drivers in ∅20+mm formats, at least for the tinkerers who aren't after extreme outputs. Drivers like the LD-29, H1-A and H2-C are among my favourites.

Fixing the SK98 may take some work, depending on whatever pill you get. If you buy a genuine UltraFire SK98 (@ FastTech, homepage link here) you'll get a hollowish pill with 2mm shelf and ≈11.1mm inner hole, not too bad for stock power output. Take a look here if you will.

By the way, seems to me SK98s do feature quite good heat dissipation, am I right? In theory my SK98 burns up to ≈25 - 26W (XHP50 at ≈3.6A) on high but it doesn't exactly gets hot super-fast.

Cheers :-)

I ordered a SK98 from Ali yesterday. The Supfire F3-L2 looks very promising too. It looks like it has a glass lens also.

I have 4 of the H1-A drivers. So yes light output is my goal. And I am just a tinkerer. A small Zoomie that will put out more light than a factory cheapo light.


I posted a couple weeks ago my upgraded atomic beam with a xhp50.2 and H1-A. Its 20mm and solid, not hollow (see pics).
I am satisfied with my mod.

Here is the link: MODIFIED ATOMIC BEAM FLASHLIGHT (w/ PICS)!!!!!!!!!!!!!!!