Amazon itself will handle the pickup of packages from sellers. In some cases, it will also handle delivery to customers, eliminating the major delivery partners of UPS and FedEx.
Those delivery companies will be used in some instances, Bloomberg noted, but Amazon will still be shipping the product to customers instead of relying on a third party to get it there.
Amazon taking greater control over the logistics of its third-party packaging gives online shoppers a more consistent experience and gives Amazon greater flexibility. It also helps to solve overcrowding at warehouses that use the Fulfillment by Amazon program, where third-party sellers send items for Amazon to store while they wait for a buyer.
Seller Flex is being tested on the West Coast before rolling out nationwide. Amazon previously tested it in India for two years.
In 2016, Amazon introduced the Seller Fulfilled Prime program, which allowed third-party sellers to sell with the Prime two-day shipping guarantee if they could prove that that time frame was feasible even if the items didn't ship from Amazon's warehouses.
This post originally appeared on Business Insider.