I have not had occasion to use it under real conditions (evening back at night ...) but so far no problem. The pros: - Battery LR6 to use (not supplied), which is better than small batteries such as watches - Strap - Look solid and sober - Light (pass excavations) The -: - Strap a little long for a key chain and quite boring to install - Button not very ergonomic, but there's no need to stay therefore supported it goes