UL Listed: For safety and certified power ratingsNG - Powered Generatorâ¢Designed for large homes & commercial buildings    â¢WILL NOT WORK with LP fuel sourceWhisper-Testâ¢Reduces sound output to 65 dB(A) from 75 dB(A) @ 7 metersAutomotive-Style Engineâ¢Quiet 6.8L Generac V-10 engine liquid-cooledAluminum Weather-Protected Enclosureâ¢Shelters generator from weather and reduces exterior noiseâ¢Insulation lowers sound levels by 2-3 decibelsBuilt-In Battery Chargerâ¢Maintains battery (sold separately) at optimum performanceAutomatic Safety Shutdownâ¢Low oil pressure, high temperature protectionâ¢Overspeed and/or overcrank protectionRequires "RTS Series" Transfer Switch (Sold Separately)WILL NOT WORK W/ "HTS Series" Transfer Switch