Fenix LD01. It fits on my ear or you can make an ear clip if not happy this way.
Best light I've ever owned. No need for heavy headlamp it fits on my ear like a pencil or you could make an ear clip for it very easily. Uses easily found light weight lithium AAA cell. Has no button or switch to wear out.
Cree XR-E LED (R4) with lifespan of 50,000 hours
Three output modes:
26 Lumens (3h8m)
3 Lumens (27h)
72 Lumens (1h28m)
Dimensions
       • Length: 75mm / 2.95inÂ
       • Diameter: 14mm / 0.55inÂ
       • Weight: 14 grams / 0.5oz
Made of durable aircraft-grade aluminum
Toughened ultra-clear glass lens with AR coating
Premium Type III hard-anodized anti-abrasive finish
If you stick it in a drill press and poor man's lathe turn it down with a file you can get it down to about 11g without going too thin but as is at 14g it's very very strong.
If you take the case off and just use the guts you can get it down to about 5 grams but it won't be very durable or water proof unless you spray the guts with epoxy.
I made one that just is a battery and led/reflector with no glass and no housings and it weighs under 5g including the paper clip it clamps around my ear with.
It is brighter and throws a beam further than any sub 5g flashlight out there and also most single cell lights period.
It is both a tea candle at 3 lumens and a search and rescue light at 72 lumens FYI. In a pinch that is.
You need to carry a brighter light with 12 hours of battery life to be considered a true search and rescue but this is better than nothing.
Buy a Fenix whatever you buy. Nothing else comes close to their models for the money.
I have a couple mods next to my guns in the house that are 1000 lumen lights with skull crackers that weigh 2 pounds and an LD01 for every room.
Buy a Fenix at REI and take it back k a year later if you hate it. Give them a shot and focus on maximum value. The more expensive lights are just the same guts in a different case with more expensive branding. Why pay more when all these different lights are made in the same factory?
Fenix isn't junk it's just not overpriced either. Ld01 is only about $20 and is rated accurately unlike other manufacturers.
Trust me I build reef lights and custom lighting for homes and home security. I can't build a light for free as good as a Fenix for the money. Fenix is the only flashlight you're not overpaying for on the market. Buy it at REI and you can't go wrong with their satisfaction guarantee.
I'm partial to Cree led bulbs too btw. They throw light further than any other led in the world and have punch/impact. The premium reef lights I build use Cree bulbs and I've seen the results on coral growth. Nothing else comes close but they are a bit spendy.