Motiv is adding heart rate-sensing security features to its smart ring that will enable it to make payments later in the year, the company announced today at CES. The ring has always measured your heart rate for the purposes of tracking your exercise and activity, but now the company wants to measure the heart accurately enough to read it like a fingerprint and verify your identity. Once your identity is verified, the ring can communicate with point-of-sale terminals to authorize payments. The functionality will be available in a new Motiv ring to be released in the second half of this year.

The device will work based on the theory that everyone’s heart gives off unique signals in their heart rates. Motiv intends to use electrocardiography (EKG) to measure them to verify your identity. The existing ring is already FIDO-certified as a means to log into your online accounts via the WebAuthn standard and as a two-factor authentication device, but this currently relies on making specific gestures with your hand while wearing the ring.

In the past, the company has also considered using the way you walk as an authentication method called “Walk ID,” but this heart rate tracking could be a much more convenient security method. The biggest question will be how accurate the heart rate tracking is, and whether the system can be thrown off by exercise or other heart irregularities.

Correction: After first telling us that they would be available via a software update, Motiv has since confirmed that the new NFC and heart rate security features will be coming with a new ring. The article has been corrected to reflect this.