The GH batteries are unique to the Hopper in size, however they are standard Li-Ion technology so can be charged using any multi size charger. Any of the Nitecore www.Nitecore.com chargers will charge the Hopper batteries as well as 18650, 18350, AA, AAA etc
Chargers are readily available from Amazon, Ebay, Ecig stores etc. I have a Nitecore D4 which charges 4 batteries simultaneously. Look out for fakes though, there are a lot of fake chargers around so buy from a reputable vendor.
Personally, I have 3 batteries but in reality 2 is plenty as they...
My first unit that failed after a month didn't flash blue at all until the third bowl just before the batteries died. The replacement starts flashing increasing in intensity almost after the first hit or two of a fully charged battery.
Not saying either is right or wrong however, my replacement...
I live in the UK and bought mine from the Hopper Labs authorised stockist Vapefiend.
I've had to test out the warranty service after approx one month of ownership the heater died.
Vapefiend deal with warranty claims onsite for purchases from them.
I sent it back on a Wednesday, it was...