Amazon MCF is a service where Amazon will ship your inventory to your customer on your behalf acting as a 3PL/dropshipper for you.
In aggregate, SKULabs can be configured to forward all or part of your orders to Amazon MCF to be fulfilled using your FBA inventory with shipping rules.
Individually, you can submit fulfillment orders to Amazon to be fulfilled from your FBA using the "Fulfillments" panel on an order. It's as easy as shipping an order regularly!
Reach out to customer support for help configuring this.