You can change your face with plastic surgery or even burn off your fingerprints, but you’ll struggle to avoid identification when the US military begins deploying its latest surveillance gadget.

According to MIT Technology Review, a laser has been developed for the Pentagon that can read people’s unique heartbeat signatures, after it was requested by US Special Forces. Code-named Jetson, the device is still in the prototype stage but is already able to read heartbeats from around 200 meters (656 feet) away, even through people’s clothing.

While other personal credential like faces, fingerprints, and irises are typically used for recognition, similarities between individuals mean that identification errors can occur. However, every person has a completely unique and distinct heartbeat profile, making this a much more reliable biometric for pinpointing individuals.

Jetson uses a technique called laser vibrometry to detect the subtle changes in the reflection of ultraviolet light as a person’s skin and clothing move with their heartbeat. As such, it can be used to identify people from a distance and from any angle, which is more convenient than current methods that require either a clear view of a person’s face or access to their fingers.

Speaking to MIT, Steward Remaly of the Pentagon’s Combatting Terrorism Technical Support Office said “I don’t want to say you could do it from space… But longer ranges should be possible.” He also claimed that the current prototype has an accuracy of about 95 percent.

However, while military officials hope to one day use Jetson to identify insurgents from drones, a few technical issues need to be ironed out before the technology can be deployed. At present, the laser takes around 30 seconds to generate a reading, meaning it can only be used on stationary subjects. Perhaps the greatest obstacle, though, lies in the fact that a database of cardiac signatures will need to be created so that readings can be cross-referenced and identified.

If this new remote surveillance method ever becomes widely used, it will surely be met with a number of privacy concerns, considering the potential it raises for spying on people from a distance. On the plus side, there’s no need to dip your fingers in acid to avoid identification anymore.

[H/T: MIT Technology Review]