E-commerce giant Amazon is testing palm-scanning payment technology at two of its Seattle convenience stores. If successful, the palm-scanning payment system could spread across the country.

Business Insider reports that Amazon is now letting customers pay at its Seattle convenience stores by scanning their palms. Amazon has begun trialing its new contactless Amazon One payment method, which links a customer’s palm print to a credit card so that they can pay by waving their hand in front of a scanner.

The palm scan also opens electronic entry gates at the two Amazon Go stores that usually require a code. The technology could roll out to more than 20 of Amazon’s Go stores as the trial continues. Amazon has also begun encouraging other retailers to sign up for the technology.

Customers can sign up for the payment method by going to one of the two stores trialing the system, entering their credit card details and mobile number into a device, and scanning their palm on a biometric reader. Amazon also stated that both user’s palms can be registered because “you never know which palm will be free when you need it.”

Amazon patented technology in 2019 that would identify people’s hands by analyzing characteristics such as wrinkles, veins, and even bones. Amazon stated that it chose to use palm prints, which it refers to as “palm signatures,” as each person’s palm print is unique and doesn’t change over time. Amazon One could also be used to identify individuals, such as when they enter offices or sports stadiums, according to Amazon.

Amazon also claims that the biometric data is stored separately from customer data. “We take data security very seriously and protect sensitive data, such as your palm signature and payment information, at rest and in-transit in accordance with Amazon’s high security standards,” it said on the Amazon One website.

“Your palm data and payment information are not stored on the device and multiple layers of security controls protect your data at all times, including, but not limited to, encryption, data isolation, and dedicated secure zones with restricted access controls.”

Lucas Nolan is a reporter for Breitbart News covering issues of free speech and online censorship. Follow him on Twitter @LucasNolan or email him at lnolan@breitbart.com