COURUI DO1 'Big Head' (Black/GRAY NOW AVAILABLE) $29.99 @ Gearbest ( use coupon: gbcourui) A long-throw modder's light!

Took new lux readings at 23.0 feet (7.010m) with new fresh alkalines in the lux meter and now I'm getting 136kcd. For comparison a stock ZY-T08 is measuring 31kcd and a stock Jacob A60 at 31kcd (both of those on fresh cells). They seem a bit low but I'd have to search and compare to others measurements.


Not sure what’s going on with your D01 but is sounds like your throw readings are going in the right directions. Your numbers on the T08 and A60 sound really low though, my A60 measured 74k stock and T08 was 77k stock.

I spent some time tonight trying to dial in my T08 focus a little better, initially made it much worse but after an hour ended up where I started.

I’m beginning to think I should just stop measuring amps and lux, just mod and if it’s brighter be happy. All this effort to gain 0.5 amps or 1k lux is taking all the fun out of this hobby.

I even used the "max" mode of the meter this time (it was getting awfully hard to read those digits from 23 feet away). My readings were also after 30 seconds. My T08 appears very bright and well focused by eye.



Here’s a pic showing the adapter ring to hold down a copper disc I made with no threading.
(I am having a bugger of a time getting good focus though) :~

So between this and the zy-t08, which one is the bigger pain to get a dedomed XP-L properly focused?

Finished my D01 tonight.

I used a Star Momentary Q-Lite +8 from Mtn, XP-L V6 3C de-domed on a Noctigon XP32 MCPCB sitting on one of the big copper discs mentioned in one of these D01 threads. A UCLp AR Lens from, Omten lock-out switch and spring braiding round out the build.

A couple of things about this build had me about ready to give up. First, and not that bad, was the amount of filing I had to do to get the top of the copper disc flat. I just left my file in the vise and every time I had the time I went downstairs and filed away for 20 minutes or so.

Second and a real pain in the butt was getting the reflector where it needed to be. Even with the 32mm MCPCB the reflector still partially covers the solder pads.
I started by taking one of those bow tie shaped gaskets and cutting the wings off so it was perfectly round, it ended up the same diameter as the opening in the reflector. I then glued it down on the MCPCB.
I had to solder, re-solder and re-solder the wires repeatedly to get all the clearance possible, even with carful filing of the reflector.
When done I used the dremel to clean up and provide just a bit more clearance for kapton tape.

All the aggravation was worth it, the reflector sits right down on the MCPCB. It is the most perfectly centered, tightest beam I have ever seen.

Lux (converted from 9 meters and relative only to my measurements):
Before mod 77k
After mod 289k

I’ll have to wait until I get up to the lake to really see what it can do, no good open areas around here.

Sounds great! So how many amps you pulling on which cells?


I haven’t checked yet, I need to rig something up again so I can check with multiple cells. The cells I used for Lux measurement were protected Panasonic NCR18650Bs that I bought for this light. Three in parallel should have no problem providing 6A so no need for high output cells with this driver.

This light is part of Gearbest’s Ist anniversary sale. For a limited time (until March 31st), the price goes down to $27.99.
Edit: and the Opus BT-C3100 v2.1 is now @ $36.78 only (among other items)

I've bought half a dozen of these lights now, all from GB. The first couple were for myself, & the rest have been for friends. All lights purchased with a view to modding.

Latest one arrived today; The build quality on this one was pretty bad... Everything that could be loose, was loose.

Lens 'o' ring too small, & poking out between lens & bezel.

LED Dome dirty & damaged.

Shelf no longer screws in tight, threads not deep enough, so it just spins.

Gouge marks at the top of the battery tubes, as if the chuck of the machine had gone too deep, leaving some nasty jagged burrs to tear up your cell wrappers...

It let the magic smoke out almost straight away; The centering ring was so thin (less than 0.5mm), that tightening the bezel slightly shorted out the reflector on both LED wires. The + wire heated up, & came off at the driver pad.

This one was definitely a 'Friday' light....

Thanks for the update FmC. Lets hope the crap copies have not started but it sure looks like it.

Hmm, not good. How was the reflector itself? The last one I had from gearbest had a nasty hazing on one half of the reflector, I just ordered another so hopefully that one will at least be decent quality.

It’s such a shame how the quality tends to drop off on all these lights.

The reflector was fine, & the driver is still the same. I’m surprised that the driver didn’t pop when it shorted.

I just received mine and everything is good but the reflector. Lots of pits and debri. The dust for a lack of a better word, won’t even clean out with compressed air. Is their a replacement reflector that can be purchased somewhere? Other than that the light has really good machining, and clean otherwise???

:frowning: Sounds like quality control on the lights is really hit and miss now

If you’d like to cover postage I could send you my partially hazed reflector, it’s clean and flawless apart from a segment of hazing that’s visible when the light is on.

Or there’s a chance I could send you a better reflector in a couple weeks. I have another courui on the way from gearbest and I don’t need the stock reflector in my next build. Sounds like there’s a good chance it will be an equally poor sample though…

Thanks for the generous offer, if you do get a nicer reflector, I’ll make it worth your effort and pay all expenses,LH! Damn shame other wise the light has great machine work. I chucked the body up and checked run out less then a thou,(.001”) bored the threads for the old plate out and made a custom 10.5mm stepped heat sink and pressed it in, so now it makes contact on all 3 surfaces, the inner diameter, the shelf and the upper diameter. Center stepped it for a 31.59mm Maxtoch mcpcb. And relieved the reflector base for additional lead clearance. It’s looks great so far,installing a BLFFETDD driver and dedomed XML2 U2 0D, we’ll see how it throws??? EDIT: MTNFETDD driver!

Hi FmC, I’m really sorry abou it, could you please PM with your order number, thanks.

Thanks Gearbest for taking care of us with your after-sales service!

I did not expect 180 units of these lights have been sold so far.

Hi Gearbest, PM sent regarding order number.

I have repaired the light, so it's not a problem for me.

However, if someone who didn't have the knowledge/tools/ability/spare parts, had received this light in the condition it was in, I'm sure they would be very disappointed.

I just wanted to bring this to the attention of other forum members.

- edit -

It's only fair to add here that Gearbest have offered me a partial refund (store credit).

New invitation from Nicola S about a pure copper pill for the Courui DO1:

Ok guys I am going to start NEW production of copper pills, this time no limit in number of them, and the price will be 23$ for Europe,and 25 for the rest of the World . Price include shipping and tracking number. Please let me know how many of you are interested this time . Special PayPall account for this sale is

L I S T :

Jensa41 (and counting)