The two most important metrics to look at when shopping for a flashlight are battery and lumens.
batteries: There are two large categories of both flashlights and headlamps: rechargeable flashlights and those that take batteries. The difference is how you recharge them. AA or AAA batteries are easy to find and can be replaced quickly. When your lights go out in the dark, you'll notice the brightness of the different batteries. That said, rechargeable lights can charge equally power Bank You're charging your devices, and these days, with USB-C, many lights can recharge in less than an hour.
I used to swear by the battery option, and I still recommend a headlamp or flashlight with a removable battery for many situations (yours). emergency kit for example), but I must say I reach for the convenience of a charging port for an everyday carry flashlight or camping headlamp. Personally, I rely on a Nightcore NU25 For most situations except long backpacking trips where I bring my own stuff Petzal Tikka And a set of spare batteries.
lumen:Flashlight and headlamp companies love to talk big about lumens, which measures how bright a flashlight is, but the truth is you don't always want more lumens. We didn't find a single flashlight or headlamp we tested that wasn't bright enough. You'll find all kinds of lights here, from 300 lumens to 1,000 lumen spotlights that will temporarily blind you if you look at them. For most uses, this is a good range: 300 to 1,000 lumens. For something like reading in your tent at night you'll want very little light, but any good headlamp will have a variety of brightness levels, usually with a low power mode that's something like 40 to 60 lumens, which is what you'll be looking for. Reading is about what you want. Also, look for a strobe mode that will pulsate the light. The strobe function is good for rescue situations because the flash is more noticeable than a steady light.
Nowadays, the light source of most flashlights and headlamps is LED. Although there are still plenty of traditional bulbs out there, it's hard to beat the light output to energy usage ratio of LEDs.