1 click - On/off at last setting
1 click, hold down - increment intensity
2 clicks - strobe at that intensity
4 levels of intensity, 630 lumens at top level.
The button is inset, but a groove is provided along the rim, so that an index finger could manipulate it instead of a thumb, and still have a thumb/finger solid grip.
The 630 lumen output strobed is totally disorienting if aimed at you. Pointing it away does not seem that bad.
The top setting. think HID car headlight. Seriously bright during the day. If you caught someone with eyes adjusted to nighttime, you would have a serious advantage.
