Group 31 batteries are the giants of this trio, measuring around 13 x 6.8125 x 9.4375 inches. They’re built for heavy-duty applications, delivering high power and long-lasting performance. If Group 24 is your commuter car and Group 27 is an SUV, Group 31 is the truck—ready to handle the toughest jobs. https://www.batteryequivalents.com/bci-battery-group-size-chart.html