Amazon Prime customers in two pilot program towns can now get their packages delivered by drone.

Amazon’s promised drone delivery service is finally available, although only available on a limited basis. The new system, called Amazon Prime Air, is now operating on a pilot basis in Lockeford, California and College Station, Texas. The announcement is significant and marks the latest step in the retail giant’s march toward ever more automation.

Amazon received approval from the Federal Aviation Administration to use drones for package deliveries in August. The maximum payload for Prime Air is 2268 gram (5 lb), and Amazon says that 85 percent of its shipments fall under that weight. This is according to a report in Ars Technica.

Here’s how it works

Residents of the two pilot towns can sign up for the service, and Amazon will then confirm that the company can deliver safely to the customer’s address. Once onboarded, customers can see Prime Air-eligible items on Amazon.com. They place their order as they normally would and receive an estimated arrival time with a status tracker. Once an order is placed, the customer gets an estimated delivery time and tracking info.

“The drone will fly to the designated delivery location, descend to the customer’s backyard, and hover at a safe height,” Amazon said. “It will then safely release the package and rise back up to altitude.”

Lockeford is a small, rural town of about 3,500 residents located about 50 miles southeast of Sacramento. This makes it an ideal location to pilot drone delivery. College Station is roughly 100 miles northwest of Houston and is the home of Texas A&M University.

Natalie Banke, Amazon Air spokesperson, described the goals of the new service. “Our aim is to safely introduce our drones to the skies. We are starting in these communities and will gradually expand deliveries to more customers over time”, she said.