the first time I use one of these be on a hike trip in the Grand Canyon . I be amaze how bright it be . my only two complaint about these be : 1 -rrb- while they be very tough when the battery be install , do not drop one while it be empty . the battery must help strengthen the tube . I drop mine and the tube dent easily . I could not get it round enough again to reload the battery . I have to buy a new one . 2 -rrb- do not let you battery get old . they fit so snuggly in the tube and if they swell or leak , you 'll never get they out .