I took more measurements and here are the lumen results for 4 different E07:
E07 XP-L HI 6500k - QSO VTC6A 6,681; 30T 6,983
E07 XP-L HI 5000k - QSO VTC6A 6,551; Vapcell VTC6A 6,379; 30T 6,733; Vapcell 40T 6,810
E07 XP-L HI 5000k - QSO VTC6A 6,586; Vapcell VTC6A 6,630; 30T 7,327; Vapcell 40T 7,017; QSO 40T 6,983; LG M50 5,353; Lishen LR2170SF 5,866; Samsung 50E 5,268
E07 219B sw45k 9080 - Vapcell VTC6A 3,707; 30T 4,301 (quickly dropping); Vapcell 40T 3,741; NCR21700A button top 2,828; LG M50 3,233; Lishen LR2170SF 3,450, Samsung 50E 3,449
For some reason, I cannot reproduce the 7,570 lumen measurement again. The unit I measured 7,570 now only makes 7,357 lumens. Not sure if the emitters already degraded from me constantly blasting turbo or is it due to some other reason. I’m surprised the XP-L HI v3 6500k unit is not as bright as one of the XP-L HI v2 5000k unit.
I think the 40T is the ideal battery for the XP-L HI version. For the 219B version, I would think the NCR21700A recessed top with 15A would be the best battery but I don’t have a charger that can charge the recessed top and the soldered button top version adds an incredible amount of resistance. Otherwise the LG M50 is not bad for the 219B. The 40T might be pushing it too hard in the long run.
Also I really like the look of this light. The knurling and the very deep and functional heat fins look great. Most of the weight is in the head of the light where it is needed most for heat sinking. Jack said he designed the final prototype with super thick 8mm shelf. I couldn’t measure it but with the optics removed, it seems the shelf is probably not that thick but without removing the mcpcb and driver I can’t say for sure. But it did look like Fireflies listened to our request to increase surface area and mass in the head for better heat sinking and dissipation.
Machining quality is not as good as the Emisar series but not too bad. The clear anodizing version is OMG beautiful and a must have for anyone’s collection. Now I’m patiently waiting for a copper version.
One suggested improvement is to find or make an optic with larger TIR cups for more focused beam. There’s too much wasted space between the cups. Otherwise, I think the size of this optic can fit 10 cups and emitters for an even more amazing flooder good for 10k real OTF lumens.
Overall, this is the best pocketable EDC I’ve seen to date. It is also BY FAR the brightest single cell production flashlight in the world. It is twice as bright as the previous record holder, which is the Emisar D4S.