I bought these to replace flashlights, and batteries. Why keep cumbersome flashlights lying around, and never can be found when needed, and worrying whether or not that the batteries are good or not. Cyalume sticks last far longer than batteries and you can place them in strategic places around the house, always at hand when needed. Rip open the package bend, snap, and shake. That's all there is to it. Safe and convenient lights whenever needed. Also great for camping, night fishing, and children saftey during trick, or treat hours. Will last upto 12 hrs, when sticks go out, simply toss in the trash can.