Obviously an absurd rating, probably closer to 600 lumens.
It's not what I'd want for EDC or even a stay at home primary use light, but if you have the 18650 cells lying around and needing a home, it is useful to have reasonably bright flashlights located where you most need them.
Just don't think that you can get a high # of uses out of any one of these. They are best for a few uses each when you need them and may require some basic tear down and cleaning to be at peak performance.
If you have spare 18650 cells, you might as well have them in a flashlight, but if this is your first foray into 18650 powered lights, average or better tend to cost $25+ each. Lower than average can work if you need longer runtime instead of more brightness, as long as you DIY the quality control and cleaning.
^ Without writing pages about it for a low value light, not that simple. T6 is a bin that can have a different average value for each model of LED, and XM-L is a 10W LED that if properly implemented, can achieve over 1000lm.
However, implementation to do that requires enough drive current, precise machining of quality material for heat conduction, and on a small flashlight, a certain surface area. It also requires higher spec driver components to handle heat produced there.
The linked site is, if measuring accurately, just telling you the observed output due to limitations other than the LED, and a quality brand may be a bit conservative of the LED output to promote longer life.
However when talking about very low priced lights, the LEDs are often fake/clones, nor a major brand like Cree.
I am 100% certain the site linked is wrong, for example nobody would use a genuine XM-L Q5 and drive it so low as to only produce 150 lumens. Cree has smaller die LED part #'s that easily accomplish more lumens than that, at lower cost, and due to the smaller die size, make it easier to create better beam focus and throw without using a much larger, deeper reflector.
There are a number of other things the flashaholic community would also consider bad advice on the linked webpage, but as already stated there is only so much, reasonable to write about for these $4/ea flashlights.
Also you can look at the LED manufacturer, Cree datasheet which gives lumen vs current values for each model and bin of LED, can measure the drive current on any particular light, and measure temperature then look at the temp vs lumen degradation graph on the datasheet. There will still be some losses out the front of a light from reflector or lens inefficiency but it gets you in the ballpark.
Ultimately, it still comes back to only being able to trust major brands' specs. There's a lot more info if you're interested. You might want to spend some time on these sites:
Comments & Reviews (6)
It's not what I'd want for EDC or even a stay at home primary use light, but if you have the 18650 cells lying around and needing a home, it is useful to have reasonably bright flashlights located where you most need them.
Just don't think that you can get a high # of uses out of any one of these. They are best for a few uses each when you need them and may require some basic tear down and cleaning to be at peak performance.
If you have spare 18650 cells, you might as well have them in a flashlight, but if this is your first foray into 18650 powered lights, average or better tend to cost $25+ each. Lower than average can work if you need longer runtime instead of more brightness, as long as you DIY the quality control and cleaning.
https://www.brightexlabs.com/blog/how-choose-best-tactical-flashlight.php
However, implementation to do that requires enough drive current, precise machining of quality material for heat conduction, and on a small flashlight, a certain surface area. It also requires higher spec driver components to handle heat produced there.
The linked site is, if measuring accurately, just telling you the observed output due to limitations other than the LED, and a quality brand may be a bit conservative of the LED output to promote longer life.
However when talking about very low priced lights, the LEDs are often fake/clones, nor a major brand like Cree.
I am 100% certain the site linked is wrong, for example nobody would use a genuine XM-L Q5 and drive it so low as to only produce 150 lumens. Cree has smaller die LED part #'s that easily accomplish more lumens than that, at lower cost, and due to the smaller die size, make it easier to create better beam focus and throw without using a much larger, deeper reflector.
There are a number of other things the flashaholic community would also consider bad advice on the linked webpage, but as already stated there is only so much, reasonable to write about for these $4/ea flashlights.
Ultimately, it still comes back to only being able to trust major brands' specs. There's a lot more info if you're interested. You might want to spend some time on these sites:
https://budgetlightforum.com/
https://www.candlepowerforums.com/
https://lygte-info.dk/review/Reviews%20UK.html
Thank you!