This stranded copper cable is UL approved. The larger gauge allows for high current with little resistance and prevents overheating of the circuit components. Use this cable for connections between batteries or between the battery bank and the inverter, power center o circuit protection distribution panel.
They are made of flexible fine-stranded copper wire with PVC insulation to resists abrasion and corrosion. This cable is rated MTW, THW or AWM for 600V systems. It is outdoor rated, sunlight resistant and direct burial. It is available with red or black insulation for your positive and negative circuits respectively.
Use 4/0 gauge cable in circuits protected by 250A breakers or 400A fuses. For circuits with 175A breakers and 200A fuses use 2/0 cable. Consider #2AWG cable for circuit protection 110A or smaller.