ODYSSEY Batteries trolling thunder marine dual purpose battery (SAE brass terminal) has both massive starting power and amazing deep cycling capability, up to 400 cycles at 80 percentage depth of discharge. With 2 times the overall power and 3 times the life of conventional marine batteries, the ODYSSEY battery is ideal for Trolling, starting, and for powering the many on-board electronic accessories common in boats and recreational vehicles. When it comes to replacing a marine battery, boat owners have traditionally had two choices, starting or deep cycle. Often this means a compromise because most boaters want both, a marine battery that delivers robust starting power when they need it, yet also withstands deep and frequent depths of discharge without significant power loss. Unfortunately, no single battery could provide both until now. The amazing deep cycling capacity of the legendary trolling thunder battery along with massive cranking power is all in one revolutionary battery. Its construction consists of pure virgin lead plates for maximum surface area and optimized recycling, AGM design that eliminates acid spills, high conductivity, corrosion-resistant tin-plated brass terminals, high integrity terminal seal, a sealed design resulting in gases recycled internally, a self-regulating relief valve, tough flame retardant cell containers and robust internal cell connections to prevent vibration damage. Compared to spiral-wound batteries of equal size, ODYSSEY batteries pack 15 percentage more plate surface area into the case. Avoiding the dead space between cylinders in six-pack designs means ODYSSEY batteries deliver more power and 40 percentage more reserve capacity.