Opel recently announced a handful of world premieres for the Frankfurt Motor Show including the Astra, Corsa, Grandland X Hybrid4 and Zafira Life.

Now, it appears the company has something special up its sleeve as they’ve released a mysterious teaser image on Twitter. The company is keeping tight-lipped, but hinted the model has an electrified powertrain as they said “We still have to hide our #electrifying secret.”

That isn’t much to go on, but the car appears to be a concept as it sports unique tires with yellow accents. That’s a relatively minor detail, but they recall the red tires used on the Opel GT concept which debuted at the 2016 Geneva Motor Show. However, we can rule out that model as it used a turbocharged 1.0-liter three-cylinder engine that produced 143 hp (107 kW / 145 PS) and 151 lb-ft (205 Nm) of torque.

Also Read: Opel Should Definitely Build The GT Concept

The colored tires also recall the more recent GT X Experimental concept which was unveiled last year. At the time, the company said the electric crossover provided a “preview of what Opel cars will be in the mid-2020s.”

The company didn’t release detailed specifications, but confirmed the concept had a 50 kWh lithium-ion battery pack and inductive charging technology. The GT X also featured a Level 3 semi-autonomous driving system.

Given the similarities to the GT and GT X, it’s possible the model is yet another GT concept. That remains unconfirmed, but we’ll find out soon enough as Opel’s press conference is scheduled for September 10th.