[chrisbalich]

Originally Posted by sugarwood

As a $13 alternative, you could just attach something to the (+) post.
You'd have to seal off the open connection somehow.
With that, you could just use traditional jumpers snice the (-) post is not blocked.
https://www.amazon.com/Spartan-Power-Gauge-Battery-Cable/dp/B0713MGL78?th=1

Then again, Walker's vice grip trick accomplishes the same thing for free.

you can seal off the positive end of a cable like ^^ with a large vacuum cap.