Heavy-Duty Fast Battery Charger provides fleet charging power with a high cranking assist rating. Features AC and DC circuit overload protection and automatic 90 minute timer with hold position. The heavy-duty fleet charger rejuvenates all standard and maintenance-free 6, 12, and 24 volt batteries with five charging positions. Equipped with a heavy-duty transformer and patented multi-diode rectifier with built-in spares to take over if one fails. UL cranking assist rating 255A, 7' D.C. Leads 4 AWG clamp rating - 500A, manufacturers boost rating 455A, UL continuous ratings 75/65/30 amp.