Amazon will let shoppers pay with their palms at all Whole Foods stores by the end of the year, the company announced Thursday.

Amazon One is a biometric technology that lets users enter and pay for items at stores by placing a palm over a scanning device. Shoppers first have to connect their palm to a stored credit card. After that, they can pay by simply waving their hand over the kiosk.

The company first introduced the technology in its Go cashierless stores, but later began adding it to  Whole Foods supermarkets. Amazon One is now in more than 200 Whole Foods locations, and the company said it will be available in all of the upscale grocer’s roughly 500 stores in the coming months.

Amazon said Thursday it’s seeing “growing demand” for the technology, with it recording 3 million uses of Amazon One.

The company has increasingly marketed its physical store technologies to third parties as part of a unit that now sits under its Amazon Web Services cloud division. Amazon has signed deals with airport stores, sports stadiums and concert venues to install its palm-based payment tech and cashierless checkout system, called Just Walk Out.

Popular bakery-cafe chain Panera Bread began testing  Amazon One at some of its stores earlier this year. And the Coors Field baseball stadium in Denver in May began letting attendees buy alcohol using the palm scanning device.