Micro miniature size - easy to use on key ring, coat zipper or D-ring. LED never needs replaced - 100,000 hour lifetime. LED delivers up to 10 lumens - bright for its small size. Parabolic shaped LED area optimizes beam performance. Easy to use rotating "on-off" head Micro miniature LED light with a non-rotating snap hook. Features a 5mm White LED that is impervious to shock. Has a 100,000 hour lifetime so it will never need replaced. Run time of up to 8 hours of declining usable output. Constructed of machined aircraft aluminum with a rotating "on/off" head switch. Includes non-rotating snap hook and 4 IEC-LR41 coin cells.