EQ-48/4 48V Universal Battery Balancer with LCD, balances 4 x 12V batteries OR any x 2.6+V batteries in series – Watts247 Wholesale
HQST 12 Volt 100Ah LiFePO4 Lithium Iron Phosphate Battery, Built-in Optimized BMS with Low & High Temp Protection, Series and Parallel Connection, for RVs, Boats, Solar System | HQST