Another mysterious Ferrari test mule has been filmed at the Italian car manufacturer’s Fiorano test track and if reports prove accurate, it could be testing Ferrari’s new hybrid V6 powertrain.

It has been two years since Ferrari confirmed it was working on a hybrid V6 but in that time, only a handful of reported prototypes have been spied putting this powertrain to the test. This particular test mule is likely sporting a new architecture from the company but has been adorned with a mishmash of exterior parts, most of which seem to have come from the 488 GTB.

The clearest sign that this is the hybrid V6 is the sound. The prototype sounds quite muted compared to the 3.9-liter twin-turbo V8 that Ferrari currently produces for the F8 Tributo. Additionally, the prototype has some light camouflage and is sporting a set of enlarged side air intakes.

Read More: Hybrid Ferrari Mule Spied, But What Is It?

Last month, a very similar-looking Ferrari test mule was spied in Maranello and had high-voltage stickers across the exterior, indicating that it had a hybrid powertrain. Look closely and you’ll notice this tester also sports these same high-voltage stickers.

Ferrari has yet to state what sort of displacement the hybrid V6 will have but it will probably either by a 2.9-liter like the Giulia Quadrifoglio’s engine or a 3.0-liter like Maserati’s new twin-turbo V6.

It also remains unclear what Ferrari model will bring the hybrid V6 powertrain to the market with. The newest Ferrari on the market is the Roma but it uses a 3.9-liter twin-turbo V8. The F8 Tributo is still relatively fresh on the market and should stick with its V8 at least until it is replaced.