Amazon will start selling the technology behind its cashierless Amazon Go stores to other retailers, according to Reuters. Amazon reportedly has “several” retailers already signed up to use the system, which is being marketed as Just Walk Out technology by Amazon. Amazon’s website for the service invites other retailers to make inquiries.

Amazon’s cashierless system uses a combination of ceiling-mounted cameras and shelf-weight sensors to automatically track customers and items as they move around a store. Once someone has finished their shopping, they can walk out of the store without needing to scan anything or interact with a cashier. Their account will be automatically billed, and a receipt will be emailed to them. Amazon launched its first cashierless store back in December 2016, and now operates around 26 locations across the US, including its first traditional grocery store that it opened last month.

The technology will work slightly differently for other retailers

According to Reuters, the version of the system that Amazon is selling to other retailers will work slightly differently from the system in its own locations. Rather than scanning an app, customers will instead insert a credit card into a gated turnstile at the shop’s entrance. These turnstiles are set to be Amazon-branded, but otherwise each location will be branded by its individual retailer. Amazon will also install ceiling-mounted cameras and shelf-weight sensors at each location, according to Reuters, and Amazon says it takes a few weeks to install the technology in a store.

There have been rumors about Amazon licensing Go technology to other retailers for a while now. Last year, Bloomberg reported that Amazon was planning to sell the technology in 2020. Reuters notes that previous reports have said airport stores could be among the first to get the new technology.

Amazon’s vice president of physical retail and technology, Dilip Kumar, declined to comment to Reuters on the business model Amazon is using for the technology, and wouldn’t say how much it was charging. However, the service could have positive side-effects for other areas of Amazon’s business, according to Reuters, including increasing usage of Amazon Web Services, the company’s cloud service.

There’s also the question of customer data, and who owns it. If a customer wants to receive a receipt via email then they will have to type their email address into a kiosk at the store, and Amazon will then associate this with their credit card information. The credit card will also be associated with their email address if they visit other Just Walk Out-enabled stores, Amazon’s website confirms. However, Kumar said that Amazon will only use Just Walk Out technology data to support its retailers.

Amazon could face challenges in rolling out its new technology to more retailers. Reuters notes that some retailers have resisted working with Amazon in the past because they see it as a competitor and a disruptor. Previous reports have also raised concerns about the space requirements needed for the system, with high ceilings apparently being essential for its cameras to function.

Update March 9th, 8:53AM ET: Updated with additional details from Amazon’s website.