First Amazon FBA Shipment

Hello, I am just listing my first amazon product. I have had my products packed in small opp bag (clear bags). Can i send this to amazon fba or do i have to have them boxed with my upc barcode on for each product?

I was under the understanding i could send the shipment straight to amazon fba as long as the individual packages were marked with the UPC i have assigned to the matching listing and they would pack those and ship them. Is this correct?

Thank you