Amazon has been granted a pair of patents for a wristband that can pinpoint the location of warehouse employees and track their hand movements in real time. The patents, first spotted by GeekWire, describe an inventory management system comprised of trackers and receivers used to monitor workers’ performance. The original patents were both filed back in 2016 but were granted on January 30th.

The proposed system includes ultrasonic devices placed around the warehouse, the wristbands themselves, and a management module that oversees everything. The wristbands also feature an ultrasonic unit that’s used to track where the worker is in relation to any particular inventory bin. If their hands are moving to the wrong item, the bracelet will buzz.

While the patent describes this tech as a time-saving system, tracking workers in this way seems dystopian. That’s especially true for Amazon, a company that has been accused of enforcing intolerable conditions at its warehouses, like timed toilet breaks, 55-hour work weeks, and packing timers that ensure a worker is packing enough boxes per hour. In January 2017, Amazon said it planned to hire 100,000 more workers, with the majority of postings for warehouse jobs.

In an email to The Verge, Amazon disputed the allegation that it times the toilet breaks of employees. In a statement, an Amazon spokesperson told us:

“The speculation about this patent is misguided. Every day at companies around the world, employees use handheld scanners to check inventory and fulfill orders. This idea, if implemented in the future, would improve the process for our fulfillment associates. By moving equipment to associates’ wrists, we could free up their hands from scanners and their eyes from computer screens. Like most companies, we have performance expectations for every Amazon employee and we measure actual performance against those expectations, and they are not designed to track employees or limit their abilities to take breaks.”

In the patent, Amazon says that storage facilities face “significant challenges” in responding to requests for particular items. “Existing approaches for keeping track of where inventory items are stored may require the inventory system worker to perform time consuming acts,” says the description. Using haptic feedback to guide workers’ hands to the right place is, apparently, the answer. Of course, this is just a patent, so there’s no indication that Amazon will actually deploy the wristbands.

Updated February 2nd, 2018 2:37pm ET: Updated to add additional comment from an Amazon spokesperson.