Each AquaPro fill cap’s built-in level indicator tells whether
the particular battery cell needs water or the electrolyte level
The integrated water trap protects against explosive transmission
of oxy-hydrogen gasses from one cell to another through the water
hose system. (Verified by German battery company Hagen, Research
results available on request).
AquaPro is made of polycarbonate. This high quality material is
more impact and temperature resistant than the cheaper polypropylene
used by most competitors.
The self-closing hydrometer access allows one to insert a hydrometer
without opening a cover that could break, get lost or be left open.
The maximum diameter of the fill-tube is 3mm (1/8”).