Lamborghini is close to announcing its next limited-edition supercar.

The information was revealed to CarAdvice by Maurizio Reggiani, Lamborghini’s R&D boss, at this week’s 2017 Frankfurt auto show.

“Soon we will present to our most important customers a new version of what we call a one-off,” he said.

Unfortunately, Reggiani said that by the time the car is revealed to the public, possibly at the 2018 Geneva auto show next March, it will be sold out.

Lamborghini tends to use its one-off models to introduce new styling elements and technology. The most recent, the Centenario, unleashed in 2016 to mark the 100th anniversary of Lamborghini founder Ferruccio Lamborghini’s birth, introduced rear-wheel steering.

Lamborghini likes to call these types of cars “one-offs,” although in reality the company normally makes a few dozen examples.  In the case of the Centenario, there were 20 coupes and 20 roadsters. Previous examples include the Veneno, Sesto Elemento and Reventón. The only genuine one-off Lamborghini of modern times was the drop-dead gorgeous Aventador J from 2012.

The one-off isn’t the only new model Lamborghini has in the pipeline. The automaker also confirmed this week that its Urus SUV will debut in December. According to Reggiani, the Urus will be the fastest SUV around the Nürburgring and able to top 187 mph.