Portable USB charger for Nikon EN-EL15 batteries

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Looking for a portable charging solution for Nikon EN-EL15 batteries.
This DigiTek USB charger is the only one I've found but comes with Digitek branded batteries. This looks to be USB type-b unfortunately but there's no alternative I could find. I do actually a few spares as well but would like to know if these are reliable.

https://www.digitek.net.in/products/digitek-duc-010-enel-15#container-fluidnew