Product: Primary Lithium Battery (Lithium Thionyl Chloride, Li-SOCl2) Model: ER2450 Specification of ER2450: 3.6V, 500mAh Dimension of ER2450: 26.5x50.5mm Weight of ER2450: 12g Operating temperature of ER2450: -55 ~85 Celsius degree Characteristics of ER2450: high energy density, hermetically sealed, low self discharge, 1000+ count