Energizer Ultimate 1.5 V AAA Lithium Battery measuring 10 1/2 mm Dia X 44 1/2 mm is ideally designed for delivering long lasting performance in high-tech applications and has 15 yrs of shelf life. Battery performs well in extreme temperatures ranging from -40 to 60 deg C and is 33% lighter than ordinary AA as well as AAA alkaline batteries. Battery ideal for military and Proessional users is sold as 2 per carded pack.