you can use any 18650 charger.....
but for best use a Digital regulated charger....example i have a nitecore i4 charger the new nitecore batteries take about 6-9 hours from new to charge just like a new mobile phone would...
I needed to charge some as someone was coming to collect 6 and wanted them charged up... 2 i put in a ultra fire 2 bay charger charged them in two hours the nitecore i4 took 7 hours....
the two i had charged in the Ultra fire i put in the nitecore i4 to see if it read the same charge... it took another 5 hours to charge up to full so what I'm saying is some c