Amazon’s Treasure Truck, the fleet of mobile pop-up shops that offers limited-time daily discounts to customers who’ve opted in, kicked off service in June 2015 in the tech giant’s hometown of Seattle. Since then, it has grown to over 100 vehicles and locations in more than 30 major cities across the U.S. and U.K., including select Amazon Books, Amazon Go, and Whole Foods Market stores. In a further expansion, Amazon today announced that Treasure Truck will soon hit the streets of four additional major metros in the coming weeks: Charlotte, Cincinnati, Columbus, and Las Vegas.

“We’ve been so excited by the customer reaction to Treasure Truck the last couple of years, from all across the country. Our customers love the surprise of what new handpicked, must-have item is on Treasure Truck each day, and being able to pick it up from convenient locations where they live, work, and play,” said Treasure Truck director Margot Johnson. “Now, we’re thrilled to continue expanding this one-of-a-kind shopping experience with more cities, offers, events, pickup locations, and vehicles — to deliver even more delight.”

The Treasure Truck’s expanded footprint comes after two years during which product inventory tripled and the number of pickup locations per offer doubled. (The top-selling deals to date are Valentine’s Day bouquets and chocolate, Sony TVs, and smart notebooks.) Amazon says that Treasure Truck is on the road an average of five days per week and that it now hosts more than 7 times the number of experiential events (like carnivals for dogs, outdoor movie nights, and product sampling days) across the country, compared with 2017.

In one particularly memorable stunt ahead of the holiday season roughly three years ago, Seattle Seahawks player Marshawn Lynch drove the Treasure Truck around Seattle selling a limited-edition “beast-mode” Echo.

Promotions like these have no doubt contributed to the Treasure Truck’s rabid following. The text messages that inform customers when a new product arrives now go out to millions of subscribers, 75% of whom check offers within 15 minutes of receiving a notification. And frequent shoppers — many of whom reside in Chicago, San Antonio, and Sacramento — stop by Treasure Truck spots more than once a week.

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Curious about the deals on tap? Sign up for Treasure Truck notifications by downloading Amazon’s Mobile Shopping app, tapping the menu icon, and scrolling down to See All Programs > Treasure Truck. Purchases are made via the app and picked up from the nearest kiosk or truck, and they can be canceled if you’re not able to get to the pickup location. (You’ll receive a confirmation email with an address post-purchase.)