These lights are small internal LiPo dual LED lights that can also take a supplemental AAA battery. I ordered the cool white 6500k and warm white “high CRI” 4000k models. Both feature 300mah internal batteries and apparently the only difference between the regular E3 and E3 Pro is the use of 7075 aluminum in the body.
Oddly the official spec sheet
severely underrates the throw for the “OPTION 2: 4000K Warm White” model, I found significantly greater throw, which makes sense as it uses the same SST-20 LEDs as the Cool White model.
The way the light works is, when there’s no AAA cell inserted it runs on the LiPo. When a AAA cell is in the light, it will run on the LiPo and automatically switch to the AAA when the LiPo falls below 3.0v. Neat system. Per correspondence with the company, the light should run on a 10440 cell as well but I don’t know how it affects brightness levels or low voltage cutoff.
Full runtime. The Cool White model tested lower than spec while the Warm White tested higher than spec. Both lights had a lot more throw than the spec sheet detailed.
Detail runtime first 5 minutes:
The light is nicely made, and feels futuristic and cool. This is the first keychain light I’ve been interested in because of it’s aesthetics as well as it’s function. It’s very small and disappears in the pocket.
Packaging is excellent
Beamshots/Tint, top to bottom: 4000k, 6500k, 4000k, 5000k. All lights are on moonlight, so tint differences are exaggerated. Generally, each light appears “white” when used by itself and tint differences only appear in comparison. I think the E3s specifically are very nice clean white with no blue tint shifts.
White wall check has some rings but outside these are completely unnoticeable.
So far I think this is a good light, it has a lot of lumens and very good throw for it’s size. It’s not a direct replacement for a larger light but it stands on it’s own very well.