This flip phone no longer works in the US (due to the 3G phaseout), but I think it should work in many other countries (see bands below). I used it for a few weeks in 2017, and I recently tested it to confirm that the battery still holds a charge. It is very small and lightweight. It is a Plum Boot 2 (model D108) which can use GSM 3G bands 850/900/1800/1900.
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