Alipay has launched a new way to pay for your KFC in China — by smiling. So far, the facial payment system is only available at a single KFC in Hangzhou, China. The company behind the technology, Ant Financial, an Alibaba subsidiary, says its Smile to Pay technology needs about one to two seconds of facial scanning with a 3D camera and a “live-ness detection algorithm” to check the identity of the person paying, who must also enter their mobile phone number to help guard against fraud. A beta version of Smile to Pay was introduced in 2015 by Jack Ma the founder of Alibaba.

“Taking the facial-recognition payment technology offline was no easy task,” said Jidong Chen, head of biometric identification technology at Ant Financial. “On how we detect when someone’s photo is being manipulated when someone is falsely impersonating another person — we prevent this by merging software and hardware by linking sophisticated algorithms with the 3D camera. We can prevent biometric spoofing.” According to Ant Financial, the algorithm can detect shadows and other features to test if the person standing in front of the camera is actually a person, and not a photo or video used to trick the payment system.

In a video detailing how the payment process works, one young woman uses the machine in a variety of different appearances — with minimal make-up, heavy make-up, and an assortment of wigs. The machine was shown to accurately recognize her facial features each time for payment.

The KFC shop that offers the facial payment system is a healthier version of the chain called K Pro which sells salads, juices, and paninis instead. K Pro was introduced in July as a way to entice younger customers looking for healthier food options.