Ferrari has used its final power unit development tokens for the 2016 season, with the team having an upgraded power unit for the Italian Grand Prix weekend.
Ferrari had considered introducing the upgrade at Spa, with dyno results showing a sigificant gain, however with both Sebastian Vettel's and Kimi Raikkonen's power units having completed just four races prior to Belgium, Ferrari felt it better to wait another race.
Their patience has also allowed for further dyno testing to ensure reliability of the upgraded engine doesn't throw up any surprises.
As well as the Italian team using the upgraded unit at its home event, it is understood that Haas will also have access to the new unit. Sauber, the other Ferrari power unit customer, has not received the upgrade but may later this season.
This means that Ferrari has now used all 32 of its power unit development tokens for the season. The FIA confirmed this morning that Honda has three tokens remaining, Mercedes six and Renault 21.