This dimmable torch of LedLenser (serie P 7QC) is (Alkaline) is sustainable, for professional use and of excellent quality. When dimmed the burning time is 25 hours (40Lm and 20m) LedLenser is a Zweibrüder brand. They manufacture a wide range of torches, headlamps and diving lamps featuring the latest LED technology as well as, in most cases, the Advanced Focus System, one of the best focusing systems available.