Longest run time between battery changes. Provides reliable power output even in cold weather. Fits the following current model Aimpoint red dot sights: 9000 series, CompC3, CompC SM, CompM2, CompML2, CompM3, CompML3, and Laser Aiming Device LPI. Also fits discontinued older models: 1000 series, 3000 series, 5000 series, 7000 series, Comp, CompC, Comp XD, CompM, CompM XD, CompML, CompML XD. Mfg: Duracell SPECS: 3-volt DL1/3N lithium battery.