Why say USB cable+adapter more convenient for charging? the charger have two parts:USB cable+adapter,you can connect between radio andcomputer for charging by USB cable when there isn’t adapter.of course, you’re also directly plug power by USB cable+adapter. A charger have two usages, which is more convenient for charging. Adapter have four types: US adapter, UK adapter, AU adapter,EU adapter, different countires, different charger type.
Some customers often choose flase charger type, Most of countries standard charger type as blow, pls choose suitable charger type depond on your country.when you travel other countries, you just need change a adapter for charging
Now Retevis most of chargers is USB+adapter,for H777 and RT7 charger,USB+adapter more advantages than integrated charger,more stable quality and increase battery lifespan and so on.pls check the detail: https://www.twowayradiocommunity.com/h777-rt7-charger-improvement-notification/