Tesla is selling 2021 Model 3s on its website that it calls “Demo Vehicles,” whose battery packs date back to 2017. The vehicles come with a small disclaimer at the bottom saying “Range figures may be up to 12% lower [than rated by the EPA] due to battery age.”

Next to that, a hyperlink beckoning you to “learn more” opens a pop-up that explains that “This vehicle was built with a battery pack manufactured as early as 2017.” As a result of their age, their range has diminished, the site warns.

Three vehicles found near Denver, Colorado are Model 3 Long Range All-Wheel Drive models that should get up to 353 miles of range but may get as little as 311 miles of range if Tesla’s estimates are correct.

Read Also: Tesla Not Honoring Previously Quoted FSD Prices On Vehicles It Has Decided To Discontinue

Tesla isn’t the only automaker whose batteries degrade with age, though. A Geotab study of 6,000 electric vehicles (from several brands) found that the state of health of an EV battery, its effective kWh size, degrades by about 2.3 percent per year, regardless of whether or not it’s being used.

The vehicles were first noted by Twitter user Seth Horwitz, who has found similar models in Austin, Honolulu, Portland, Los Angeles, Miami, and elsewhere. Most vehicles have small amounts of mileage, mostly less than 1,000 miles (1,609 km).

Quite why Tesla has decided to use these old stock batteries is not clear. The company’s construction of Model 3s was certainly hampered by issues that year, which Tesla’s CEO called “production hell.” That has led some to wonder if these vehicles are using batteries that were never sold due to those problems but without a Tesla press relations office to ask it’s hard to know for sure.

As reported by Jalopnik that covered the story, the question of how warranties will work is also unanswered. Tesla offers an eight-year 100,000 miles warranty for its vehicles’ batteries with a minimum of 70 percent retention of battery capacity. Whether or not that will extend remains unknown.

We have reached out to Tesla for comment via its listed press relations email address and through Twitter and will update this story if the company responds, but don’t hold your breath as all of our previous attempts to contact the company have gone unanswered