Stop removing caps and guessing water levels. The Flow-Rite Pro-Fill system replaces every vent cap on your two 6V batteries with automatic shut-off valves linked by a single fill tube -- one connection, all cells filled to the correct level, every time. Designed specifically for standard 6V batteries with 2.7-inch center-to-center cell spacing.
Flooded lead-acid 6V golf cart-style batteries -- like Trojan T-105s and similar deep-cycle cells -- power most RV house banks, but they demand regular watering. Under-watering shortens battery life; over-watering causes acid overflow and corrosion on cables and trays. The Flow-Rite Pro-Fill BG-U12V-1A eliminates both risks with precision automatic shut-off valves that stop flow the instant each cell reaches the correct electrolyte level.
The universal design fits a wide range of standard 6V flooded batteries. The kit is sized for two batteries (four cells total on a pair of 6V units) with 2.7-inch center-to-center cell spacing -- matching the most common 6V deep-cycle battery cell pitch found in RV, solar storage, and marine applications.
Float-controlled valves stop water flow precisely at the correct electrolyte level -- no overfill, no spills.
Connect your water source once and all cells fill simultaneously. No cap removal, no individual cell access needed.
Designed for standard 6V deep-cycle batteries with 2.7-inch center-to-center cell spacing.
Valves thread directly into existing vent cap openings -- no drilling, no battery modification required.
The BG-U12V-1A kit contains everything needed to equip two standard 6V batteries:
Note: A hand pump, battery watering gun, or dedicated water supply hose is NOT included. Flow-Rite offers compatible pumps and guns separately (sold individually).
Inconsistent manual watering is one of the leading causes of premature deep-cycle battery failure. Cells that run dry even briefly suffer irreversible sulfation. The Pro-Fill system makes correct-level fills so quick and clean that owners actually do it on schedule -- typically every 2 to 4 weeks during active use or after every significant discharge/recharge cycle.
This kit is engineered for flooded (wet-cell) lead-acid deep-cycle 6V batteries with standard vent cap openings. Common compatible batteries include:
This kit is NOT compatible with sealed AGM, gel-cell, or lithium batteries. It is designed for flooded batteries only.
Flow-Rite offers Pro-Fill kits for different battery bank configurations. The BG-U12V-1A fits two 6V batteries wired in series (the most common RV house bank setup producing 12V total). If your bank has four 6V batteries, you will need additional kits or a larger kit designed for four-battery banks. Cell spacing varies by battery brand -- always confirm your battery's center-to-center cell measurement before ordering.