Combining the new, compact Mini ACR (Model 14152557) with the proven design of the m-Series Dual Circuit PlusR battery switch (Model 8646309) The Mini Add-A-Battery offers a more compact system for battery switching control and automated charging for systems up to 65A. Just as in the larger 120A Add-A-Battery (Model 8646275) the Mini ACR combines batteries for charging, automating battery charging, while the Dual Circuit Plus switch isolates engine and house circuits, but lets you manually combine circuits for emergency starting.