Just a word of warning about the "Vector" brand jumpstart batteries.
The darn thing takes 2 or 3 days to develop a full charge and if you
let it sit a couple of weeks without use, then you have to charge it
again.

Either I got a defective battery or the thing is nearly useless since
it requires so much time to charge and then loses the charge so
rapidly in storage.

My older Target Greatland 7 Ah is still gowing strong after 3 years
and works great. Recharge time is minimal and it holds charge well in
storage.

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Michael McCulloch