I have 2 large 48v battery banks for two seperate renewable power systems,the battery banks are GNB pdq23 2v run in series, 1300ah each. I installed these desulfaters 6 months ago and they run 24/7/365 I have seen a difference in the system since.I also orderd one for my 48v golf cart wich is also hooked up 24/7 and I noticed a BIG difference in the duration of the charge. I was sceptical at first but after 6 months running... I vote A-1 and well worth the money.
Don Sturgis,Clarkston, Michigan