Unfortunately the boosters can get wrecked if the battery is reversed and a single button press is made.
They don't have reverse polarity protection. Fortunately this is a warranty-able issue.
I'm not saying this is what happened but I believe it's the most common cause and a mistake that is easily made.
The only other issue I've had with them is shorts due to over-tightening. This can be resolved by putting an o-ring over the connector.
The o-ring should sit below the external eGo threads and this will help prevent over tightening.
Thanks for the tips. I will definitely add the oring and be extra careful with batteries
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