Jumper cables? Nah....there is a newer better solution.

mopowers said

That's very similar to the one I have. It works great! Don't expect it to turnover an engine with a completely dead battery. It's perfect if the battery just needs a little extra juice though. Mine's saved my *** a couple times - though I still carry jumper cables. I top off the charge every time I do an oil change as an easy way to remember.

Click to expand...

I wanted something to take along on road trips and to boost a car here in the backyard that is not dead but just below the point of cranking over. I was surprised years ago when I saw this chart:



Until I read this, I was under the impression that battery voltage and percentage was linear......like 6 volts meant it had 50% charge. Learning that is is at 50% at 12.06 really surprised me.