Guareentees your diesel engine will start up instantly in temps as low as -40F, even with dead batteries 1.5X the lifetime of the other batterys in the system by taking the brunt of the load when starting a truck Extends life of starter and alternator by providing adeqate power when normal batteries cannot Saves fuel by ending the need to idle truck at night to ensure battery start up in the morning Ends the need for jump packs and jump start service calls