The Rolls Surrette Rolls Surrette 2YS31PS (2-YS-31PS / 2YS-31PS) is a 2 volt battery rated at 2,430 amp Hrs. @ 20 Hr. rate. This battery is a very high capacity battery with New Generation series 5000 advantages and features. Dual case, replaceable cells, small foot print and an expected life of 15 -20 years. This battery is a quantum leap from the performance and longevity provided by golf cart and L-16 floor scrubber types. Warranty is 10 years (first 36 months replacement, next 84 months pro rated.) This is a serious battery for large systems offering muscle performance over a long service life. For a Single String 2,430 AH Bank @ 20Hr. rate, you will need 6 of the 2YS31PS (2-YS-31PS / 2YS-31PS) for a 12 Volt System, 12 of the Rolls Surrette 2YS31PS (2-YS-31PS / 2YS-31PS) for a 24 Volt System and 24 of the 2YS31PS for a 48 Volt System. Each additional string will multiply the AH. Real world expectations: The Rolls Surrette 2YS31PS (2-YS-31PS / 2YS-31PS) will support a 25 amp load for 129 hours!