My boat is 18 months old and has a Sterling "Alternator to Battery" charger, a Sterling "Battery to Battery" charger, a Sterling 3KW Pure sine wave combi unit/Inverter and several remote control stations. All worked faultlessly until recently when the charger section of the combi unit would ocasionally trip spuriously when on shore power.I contacted Sterling who asked me to return it to them which I did and they immediately replaced it with a brand new one under warranty. There kit carries a 2 year warranty and is something well worth concidering when buying expensive new equipment. Hope that helps. tosher