Portable emergency jumper pack.

[Boyntonstu]

I have used 4 Walmart jumpers that I got at a bargain price of $30 each.

I used them on a 48 Volt  electric bike that I built.

A nice thing to carry in your van for a jump start.

Many brands and prices available:

[video=youtube]

 

[dextours]

I have had many of the jump starters with the old fashion sealed batteries. Hated them all. Without constantly checking and recharging they were likely to fail you. 

If you are shopping for a jump starter  buy one with lithium batteries. They hold charge much longer. Much more reliable than the old sealed batteries.

 

[Boyntonstu]

I have had many of the jump starters with the old fashion sealed batteries. Hated them all. Without constantly checking and recharging they were likely to fail you. 

If you are shopping for a jump starter  buy one with lithium batteries. They hold charge much longer. Much more reliable than the old sealed batteries.

The jumper in the video and all the others of that size are lightweight Lithium.

I my experience, they hold a charge a very long time.