Designed for serious anglers and marine pros, the Norsk 16V 135Ah Heated Lithium Battery delivers powerhouse performance and worry-free reliability. With built-in heating, Bluetooth monitoring, and energy-saving Deep Sleep mode, this advanced LiFePO4 battery is made for long days on the water in any conditions. Lithium Iron Phosphate (LiFePO4) deep cycle battery 135Ah high-capacity design for marine electronics Nominal 16V output with 17.75V max charge Thermal Core Heating Technology for cold-weather performance Max continuous discharge current of 135A Bluetooth-enabled with Norsk Guardian App compatibility Deep Sleep BMS for power conservation when idle Group 31 size: 13" x 6.81" x 9.25" with 44 lb weight Over 4,000 cycles and 15-20 year design lifespan