From my searching I found the “Nitecore SRT7 Revenger” that proves they exist, but they are spendy and there are few out there. Maybe a talented BLF member wants to tackle designing the next ‘A6’ that uses a dial to turn the brightness up and down rather than using a button, user training, and an OTC. Thoughts? [Just the thoughts that agree with mine of course :bigsmile: ]
A magnetic control ring requires considerably more sophistication both mechanically and electronically. There’s a reason you don’t see them on budget lights.
I haven’t taken one apart, but a hall detector is around a dollar, and some tiny magnets would be cheap too. It’s a bit more work, but it’s the kind of interface an average shopper would prefer.
Not sure what your idea of “budget” is but Sunwaymans v11rs can be bought quite reasonably. It’s a great little light with a mag ring
http://www.illumn.com/sunwayman-v11r-xm-l2-216-lumens-1-x-cr123a.html
That does look like a great flashlight, except turbo is only 500 lumens and a modded driver does not exist.
Search for “mc10”
That is not variable, the dial has 4 positions…
4 modes, Strobe-Low-Mid-High
Wasn’t there a groupbuy for an imalent with this function?
Why can’t you just use a potentiometer?
It’s hard to make that waterproof.
Imalent is like $150 and a review I saw showed the light levels are hard to choose on the low quality touchscreen. It’s too small of a screen to have such a low responsiveness.
There are some “dive” lights with a linear magnetic slider to regulate the brightness and some others which have a simple reed contact which you need to slide back and forth to adjust some different modes.
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I wanted forever one of the small 18350 lights with a magnetic slider but it seems that there are no new revisions made since quite a while.
I guess that it could be done mechanicly fairly cheap from a good factory like the convoy with good tolerances but then you have to make a new driver and it seems that this is often the point in which the cheap companies invest to less money…
it was imalent dm21. i don’t remember if it was freeme or madmax that had a coupon for it a couple of months ago. but now it’s $55 http://www.banggood.com/IMALENT-DM21-CREE-XM-L2U4-USB-Charger-Waterproof-18650-LED-Flashlight-p-994338.html
The Imalent DM21 is very interesting. I don’t know what I think of the presence sensor in back, it seems it would get shut off or turned on by accident.
If you can’t find perfect light, build one 
The 2 AA Explorer E83 is on Cnqualitygoods for $30ish
has 4 illumination levels
Kaidomian has the single AA Explorer E84 with 5 Illumination levels…l
Here’s a link to a Review of the single 18650 Rocher MC10 by FreeMe,
and a linked site that carries it.
( also with detents, not infinite variability)
BTW- my Niteye Eye10 is a favorite EDC.
IT has 11 (?) detents for great illumination selection, and great output with a 18350
It’s not so much the number of levels, it’s the way you use it. With a ‘volume knob’ you can move up until you meet the point where your eyes are currently adjusted. With levels, you end up going past one too many I notice. Mine have 5 levels now.