Compact everyday carry light that accepts a single lithium or alkaline battery, with High/Low/Strobe modes Uses one CR123A lithium battery, one AA alkaline, or AA lithium batteries Ultra-bright white LED, impervious to shock, with a 50,000 hour lifetime Run time with CR123 Lithium Battery: High 1 hour 30 minutes, Low 14 hours, Strobe 3 hours; Run time with AA Alkaline Battery: High 1 hour 20 minutes, Low 7 hours 30 minutes, Strobe 3.5 hours; Run time with AA Lithium Battery: High 4 hours 15 minutes, Low 14 hours, Strobe 8 hours Overall Length: 4-1/2 -Inch