Direct manufacturer in China, a subsidiary company of Ultralife Batteries(ULBI on the NASDAQ) . Model: ER26500, Primary Lithium Battery, Lithium Thionyl Chloride, Li-SOCl2 Specification: 3.6V, C size, 26.5 x 50.5mm, 8Ah Weight: 52g Operating temperature: -55 ~85 Celsius degree Features: high energy density, hermetically sealed, low self discharge Equivalent Models: Tadiran TL-4920 Saft LS26500, Vitzro Cell SB-C01, SB-C02; Two types are available: 1) Energy type--for normal drain, ER26500 2) High power type--for high rate drain, ER26500M Other product of the same chemistry: ER14250(M) , ER14505(M) , ER14335(M) , ER17505(M) , ER18505(M) , ER26500(M) , ER34615(M) All Products have passed UL and UN.