Thanks for this thread!
I can’t advise about the 15x LED but this reminded me that I have the same flashlight in a single emitter version that Harbor Freight sold many years ago, It’s also the 3x C battery configuration and looks exactly like the 15x LED one you have, except the head looks slightly different. It’s long discontinued and was replaced by the 15x LED version, which apparently is now also discontinued. (it’s not showing on the website) I did see the 15x LED in the store a while back and wondered about it too (can’t remember how much it cost) and that was the last time I thought about my single LED version.
I liked the light greenish color shiny aluminum body and rubber hand grip, I always thought it was such a great flashlight, it was very bright with a far reaching spot beam. But this was before I began getting deep into lights about 7 years ago…
It was chucked in a box and long forgotten many years ago. As soon as I read your post and remembered having it I immediately went and dug it out, hoping I didn’t leave batteries in it! (which luckily I didn’t) I unscrewed the head and much to my surprise it has a standard 20mm star mcpcb! It has “LUMILEDS” printed on the board, (Philips/Rebel/Luxeon?) It sits on an aluminum pill that is threaded into the body tube. But trying it tonight and seeing its weak bluish beam it’s hard to believe I actually thought it was great!
It’s DD, 0.00 ohms between the (+) emitter lead and the contact board in the bottom of the pill, and the (-) emitter pad is soldered directly to the pill. There’s a spring between the contact board and switch.
Just for kicks, since the 3S cells = 4.5v (3.6v with NiMH) I began thinking about a simple emitter upgrade, using an XM-L2 led/mcpcb that I removed from another light. Also maybe bypass the contact board spring or just remove it and wire the board directly to the switch. It has a deep SMO reflector (which appears to be plastic) but has a ringy beam, so maybe some DC-Fix would be the ticket.
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Some NiMH cells I was looking at for it: