nam.64.....I was having issues with a lot of battery acid build up in my battery bay. I added the caps which helped some with recycling the acid, instead of puking it out. I also added the Demister battery oil which also helped. Between the two products, they knocked down about 90% of my excess battery acid.
The real solution came when I replaced the batteries after 6 years. I called my Inverter/Charger company (Magnum) and found that my inverter/charger settings were wrong and were overcharging my batteries. I also added an automatic watering system when I put everything back together. Once I corrected this, my battery bay turned completely dry. I eliminated the oil and the caps.
If you're battery charger isn't adjustbale and is a basic unit, I would spend the money on the automatic watering system versus the caps. The auto system seals the batteries as well as the caps, plus you gain the watering system.
Don & Mary
2014 Newmar Dutch Star - All Electric - 450 ISL
2016 GMC Canyon 4WD Crew Cab