One thing I've noticed with the zippys is that their shrink wrapping is not great. I have blue H packs and the green ones. I had to wrap electrical tape around the green packs to keep the cells from shifting. On the H packs where the wire exit, the shrink wrap eventually cuts into the wire insulation.
I was about to connect one of the H packs to my cordless weedwacker when it shorted rsulting in the following photo. No flames just a ton of smoke. Only 2 cells (6s pack) vented. Overall the performance have been great but I'd recommend re-doing the packaging especially if off-roading or jumping.
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