You can create packagings: a packaging is a set of package dimensions (width, length, height), allowing you to quickly identify the size of shipments. You don't have to specify the exact package size every time you create a shipment: you can simply refer to an existing packaging configuration.
In the left menu bar, find Management, and select Packaging.
Click New packaging.
In the Name field, add a human-readable name. This is used only to help you identify your packaging on the Admin Dashboard.
In the Handle field, add a unique identifier. This is used by the API to refer to the packaging.
If you want to use this packaging for your shipments by default, toggle the Default option.
Set the packaging dimensions in meters:
Width
Length
Height
You can use fractions when setting the size.
Click Create.