Princeton Tec Scout headlamp. Very simple: you could angle the unit; it had low, high and flashing LED (no red LED). Push-button switch. The greatest thing: there was a small lip on the baseplate rim. When you pushed the unit against the baseplate (no angle), the push button nestled under that lip on the rim. No way it could turn on accidentally. (I recently found one on eBay, so I’m good for several more years.)