I have four Trojan T-125 GC2 6V batteries. I bought one 24 volt kit and one hand pump.
The number of vent covers relates to the number of battery cells (2 volts per cell). Look on page 4 of the manual.
The are two type of kits. Clampless and snake. The "clampless" has rubber hoses that you cut to length and press onto the vent fittings. The "snake" has what appear to be plastic hoses with vent fittings pre-installed at fixed lengths.
I thought clampless (rubber hoses) would fit better because I decide the length.
Also I thought rubber hoses would be less likely to crack from water freezing in them.
Regarding freezing, read the next paragraph down from the one you quoted.
Before freezing temps arrived I hooked up the hand pump, with NO water, and squeezed several times to push air through the hoses to purge any water in them.
A local golf cart dealer ordered it for me.
On edit, if you have batteries at two different levels, ( 2 up and 2 down) the watering might work better with two separate 12 volt kits and one hand pump. That way the hand pump won't be trying to pump water up hill. The hand pump connects to one connector on each kit. With two kits and two connectors, you can water the upper batteries separately, then water the lower batteries. The hand pump is disconnected and stored separately until needed next time.
I am assuming you have 6 volt batteries. If 12 volt, then that changes the number of vents needed.
Chris and Pat
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