A shipping module access key is used when you wish to activate Shipmondo's shipping module on your webshop.
Go to your Shipmondo account and then to Settings > Integration > Shipping module access, and click on Generate key.
Copy the shipping module key that's just been created and insert it in the your shipping module setup on your webshop.
If you want to set up Klarna Shipping Assistant with Shipmondo, then you will need the identifier key in addition to the shipping module access key. The identifier key can be found right under the shipping module access key.