This rechargeable battery pack Li-ion from LedLenser 3,7V 1400mAh is sustainable and is tailor-made for each customer. This pack is compact and strong. 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.