12V Qwik-Fill kits by Flow-Rite Controls with work with most group 24-31 deep cycle batteries.  
The standard cell spacing and cell hole diameter for these batteries is 1 5/8" from the center of
one cell to the center of the adjacent cell in groups of three x .75" dia.  The height of the valve assembly (Yellow Area) is 1.25 " above the battery top surface.  See below.

For Deka EV31 and GEM 12V batteries with small circular caps see our Aqua-PRO solution

Convience-

• Hard to reach batteries are as simple to fill as batteries on a work bench
• Simple Hand Pump Operation
• Use with any distilled water container
• No need to remove vent covers
• Up to three batteries can be filled from the same fill point
• Quck disconnect features allows supply to be attached in a SNAP!

Safety-

• Remote watering eliminates hazars of conventional filling
• No need to open remove and replace vent caps
• No risk of acid splashes or dangerous fumes
• Flame Arrested- prevents external spark or flame from igniting flammable cell gasses
• Proper electrolyte level provents dangerous acid bubble out during charging

Performance

• Automatic shut-off prevents over ar under filling
• Provides electolyte level accuracy withing 1/8"
• Proper electrolyte level improves battery life
• No more bubble boil over keep electrolyte  acid/water mixture consistant