Amazon’s Just Walk Out technology is all about picking up an item and just walking out of the store without stopping at the checkout.

The technology uses radio frequency identification, known as RFID, to track your purchases when you leave the store. Amazon first tested the system at the Climate Pledge Arena in Seattle and is now continuing to test it.

Each item, now mostly clothing, receives an RFID tag that looks like a regular clothing tag. Shoppers walk into the store, select what they need, and go through the “exit gate” that scans the tags and calculates the bill. They then scan their credit card or wave their palm over the Amazon One scanner and leave.

RFID tags have long been a staple of the industry for tracking people and things: they are a convenient way to quickly check inventory in a warehouse or protect luggage from loss. Amazon is just trying to take this technology and apply it to everyday shopping.

Going through a scanner before you leave may not seem as cool as just walking out of the building, but Amazon’s advantage here is that it will be significantly easier for companies to implement an RFID system. Instead of connecting their buildings with an expensive CCTV system, they can simply swap tags, add a few gates, and you’re done.

Amazon says its Just Walk Out testing has shown a huge increase in customer traffic due to shorter queues and more transactions because the process is so simple. More than 150 stores, according to the company, have already turned on this technology.

Recall that Amazon has launched an AI tool that creates product listings. The company wants to simplify the process to “just one step.”