One inch head size?
Idk about their head sizes, I just have a P5r.2 which has only 270lm but 240m throw which is more than most 18650 reflector flashlights. And it uses a 14500 battery.
1/4 the lumens but more throw? Clearly it is not “losing” lumens, it is “focusing” them forward.
What’s great about this is that the battery lasts almost 4h on max, unlike reflector flashlights which only reach 200m+ when on turbo and only lasts an hour or so.