TAMPA, Fla. (WFLA) — Amazon is celebrating a major shipping milestone by rolling out a new feature that will allow users to thank their delivery driver through their Amazon Alexa devices.

In celebration of delivering 15 billion Amazon packages in the U.S., the major online retailer developed an Alexa feature that allows customers to directly thank their drivers for making their deliveries.

“Starting December 7, any time a customer says ‘Alexa, thank my driver,’ the driver who delivered their most recent package will be notified of the customer’s appreciation,” Amazon said on its website.

“In celebration of this new feature, with each thank-you received from customers, drivers will also receive an additional $5, at no cost to the customer. We’ll be doing this for the first 1 million thank-you’s received,” the company added.

Amazon says the five drivers who receive the most customer “thank-you’s” during the promotional period will also be rewarded with $10,000 and an additional $10,000 to their charity of choice.

“This new feature is available to U.S. customers with an Alexa-enabled device (Echo, Echo Show) or the Alexa or Amazon Shopping mobile apps,” the company said.

Drivers can be thanked multiple times, and customers who don’t have an Alexa device can still participate by thanking their delivery driver in the Alexa or Amazon Shopping mobile app.