[IP67] Im not sure what tech Fenix uses, but this seems far brighter on the max setting than any other light this size I have seen. I like the various methods of turning it on and setting intensity, it is impossible to light it up by mistake and kill your battery. So small and light it is practically unnoticeable as a carry.

[2.3-50 Hours] I am very happy to have found a flashlight with a brightness that is no other.

[IP67] I loved the E01 v1 and now love the V2. I didn't want a complicated light with lots of modes at the expense of complexity and a shorter battery life, but this is where the V2 shines. If you want to use it just like the V1, you can. If you twist it on, you initially get the 5 lumen mode and it lasts 25 hours on that mode, which is better than the 19 hours for the V1. In order to access the other brighter modes (which admittedly are definitely useful sometimes) you have to twist the cap again within 1 second. Otherwise, you get the 5 lumen mode until you twist it off. That lets you use it just like the V1 (with better battery life) unless you intentionally multi-twist it to get the higher output modes. That's the best of both worlds!

[IP67] We bought this for daytime biking. The mount is easy and locks solidly, we tested battery life immediately until it died and daytime flash was exactly as advertised 14 hours, charging was fairly fast. 150 lumen brightness in flash makes you easy to see, though if available i would go for 250-300 lumens with a slightly wider beam. Good value for money. We are pleased with the 2 we bought. And as always B&h service and delivery time was superb.

[Aluminum] High light power.
Wide power options

[2.3-50 Hours] I bought this to replace the hard wired headlamp on my e-bike, when the wire snapped. I figured I’d try this, and if I didn’t like it, I’d get out the soldering gun and hard wire a new light onto the bike. No need! This light is much brighter and has several modes. And with the easy disconnect, my son takes it off and uses it for a flashlight when walking our dog at night! Great purchase!

[3.3' / 1 m] It does run for about 25 hours, I have tested it (indoors) for about 23 hours and it is still going in fact it seems brighter than the one with a new battery but that can't be. It still can turn to a brighter setting, but not surprisingly it isn't as bright as the one with a new battery (see pictures).

It is fairly easy to operate, just twist on. Once on just twist on/off quickly to increase from 5 lumens to 25 lumens, and repeat to progress to 100 lumens. I find holding by the top and twisting with the bottom hand keeps my hand out of the light so I can see when it is off/on. [Not sure about one handed operation. If you tighten it just before it turns on, I can turn it on between my thumb and finger, with it nested in a fist like grip with my other fingers, with more effort I can turn it so it stays on. I usually unscrew it quite a bit to prevent drain, not sure that helps. But one handed would not be worth the bother, if this is what they mean.]

It can roll off a table it not attached to something, and the hole to attach it to something is very small, I think it comes with a wire ring though to put on it, or those camera straps with a final wire like ending will fit (what I am using right now)

I like the brightness levels and run times , but that varies by use/person. It is a bit bigger and heavier the rechargeable Nitecore I also bought, so by weight anyway a couple of those might beat out this one, or recharging it on a brick. This is about 1 oz with the battery and the Nitecore is 1/3 of an oz so not that much for either.

I have owned this for a couple of weeks so . . .

(I decided to test the runtime after thinking the lumens were not as bright as others but I think I was wrong about that, but I did do the test and took photos after each 5 hours of use, but the comparison at 23 hours (not dead yet) and new is probably the most meaningful)

[2.3-50 Hours] Great key chain light not much larger than the AAA battery it uses. You can carry this lightweight light in your pocket, purse, briefcase, or on your keychain and never know it is there. Nice light levels at all three settings.
Build quality is excellent. It has a good quality metal sleeve so you know it will last. It also has good runtimes at the lower levels and is easy to operate so you know it will be there when you need it. I carry mine in my pocket always.
Also, it makes a great gift.

[0.935 lb] This Fenix headlight provides plenty of light for most night rides with a very wide beam coverage. The lights build quality is excellent and the handle bar mount is solid. No reason to spend way more for a higher output light. This light is great for the price. Highly recommend and fast delivery by B and H!

[2.3-50 Hours] I bought this to replace a lost Surefire Titan Plus. Not quite as slim, but the 4x higher lumen rating, lockable switch, battery indicator, and the USB-C rechargeable battery are great to have. My only quibble so far is that the charging port cover can be hard to open if it has been pushed down into the flashlight body. Otherwise, perfect for me.