After an order management staff has assigned items in order to suitable sources, the warehouse staff in that source can create instant shipment (without going through a complicated pick-pack-ship process).
First, you need to go to the Order Details page of that order. If there are items in the order that have been assigned to the current source, the staff will see the Config Shipment section.
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Here, you can select the Carrier, Service, Title, Package Type, Weight for your shipment.
Carrier: If you are not using any integrated online shipping service with Magento, you may not need to care about this field, just select “Custom”.
We have integrated with Shipstation, if you are using that function, you can have a look in this article {Link of the page}
Package Type: You will select the package type you are using for the current shipment from a list of Package Type. Learn how to set up package type in here: {Link of the page}
Weight: Tracking the Weight of the shipment may be important as it is one of the factors that decide the shipping rate.