If you have purchased a physical SIM card, you will receive a multi-cut SIM that can be turned into a Standard, Micro or Nano size SIM (depending on what’s required for your device).
For devices that require a Nano SIM card (the smallest of the three sizes) for example, simply push out the center of the SIM to change it to the correct size.
As long as your device has space for a physical SIM card, your Mobal SIM can be converted to the correct size and so there is no need to worry!