Monster Marine Lithium(TM) "Viper" 12V a 40Ah Portable Bluetooth Deep Cycle Lithium Battery Model: MML-CW1240B Overview Portable, lightweight, and efficient - meet The Viper, a compact 12V lithium battery built for versatility and reliability.Weighing only 13 lbs, this battery is perfect for powering your 12V electronics, kayak systems, or outdoor power setups, delivering high performance in a small footprint. Built with Lithium Iron Phosphate (LiFePO) technology, The Viper provides twice the power, a fraction of the weight, and four times the lifespan of traditional lead-acid batteries.It features Bluetooth monitoring via the MMLithium App (iOS & Android), allowing you to track voltage, state of charge, and overall health in real time. Installation is simple - a true plug-and-play setup - and up to four batteries can be wired in series for higher voltage systems.Compact, rugged, and dependable, The Viper is also perfect for ice fishing bundles and mobile power boxes. Key Features Lightweight, Portable DesignAt just 13 lbs, The Viper is built for mobility - ideal for kayaks, ice fishing, go-boats, and small 12V setups. Reliable Deep-Cycle PowerDelivers 40Ah of steady 12.8V power - perfect for fish finders, sonar units, and outdoor gear. Bluetooth Smart MonitoringStay informed with real-time tracking through the MMLithium Bluetooth App on your phone. Advanced LiFePO TechnologySafe, stable, and durable - with 4000+ charge cycles and consistent voltage output under load. Plug-and-Play SetupQuick and easy installation - connect your power leads, and you&';re ready to go. Supports series and parallel wiring for expanded systems. Charger CompatibilityCompatible with AGM marine chargers (use AGM setting): Minn Kota (Precision & Digital) Dual Pro NOCO Real Pro ProSport Specifications Category Details Weight 13 lbs Dimensions (L x; W x; H) 7.5 in x; 5 in x; 6.5 in (195 x; 130 x; 154 mm) Nominal Voltage 12.8 V Nominal Capacity 40 Ah Energy 512 Wh Charge Voltage Range 14.4 - 14.6 V Max Charge Current 40 A Continuous Discharge Current 60 A max Battery Chemistry Lithium Iron Phosphate (LiFePO) Cycle Life 4000+ cycles Terminal Type M8 Bolt Configuration Options Up to 4 in series for 48V max / parallel for higher capacity Bluetooth Functionality Built-in Smart Monitoring via MMLithium App Applications Use Case Compatibility Primary Use Portable power for 12V electronics, kayaks, and ice fishing setups Voltage Systems Compatible with 12V, 24V, 36V, and 48V configurations Other Uses Fish finders, sonar units, power boxes, camping, and outdoor setups Replacement For 12V AGM or lead-acid batteries Weight Advantage Roughly 70% lighter than standard batteries