As it is clear from the name that this is for Export/Import CSV file. If the seller wants to import the dimension of the product on the app he/she can do this through any CSV file.
Please check the following screenshot:
Export product: Seller can download the CSV file format from here and update the product’s dimension (in inch) in the same file and save it.
Import Product CSV File: Further, after updating the details, the seller needs to import that file from here.
All the data in the CSV file imported on the app successfully.