The eSIM for Vietnam provides you with access to 2 to 40 GB (depending on the plan chosen), without physically changing the SIM card in your phone.
The eSIM plan is valid for 28 days, starting from the day you start using the eSIM in Vietnam.
In order to purchase the eSIM, just complete the transaction here and an eSIM QR code will be emailed to you in the next 30 minutes with instructions to install on your phone.
Once installed, you can start using data on the eSIM in Vietnam immediately. The validity of the eSIM shall start from the day when you start using it in Vietnam.