Found this:
From a SIM card format perspective, it's the same 4FF "nano" format SIM card (same size), the device does work on 4G band as well yes. Just like mobile phones, if you have 5G SIM+phone and there's no 5G in range it will fallback to 4G. If you’ve got a 5G device but only got a 4G SIM card, it will still provide signal and connectivity.
https://meraki.cisco.com/product-collateral/mg-cellular-gateways/?file
On the last line on the last page of this datasheet, there's a link to a detailed spreadsheet of Band compatibility – this will show everything in (a lot) of detail, per provider as well.