Pirelli have revealed the three compounds of their radically different 2017 tyres that will be used in next year's season-opening Grands Prix in Australia and China.
The Italian tyre manufacturer will make the purple-marked ultrasoft tyre available in Australia for the first time, alongside the red-marked supersoft and yellow-marked soft.
The supersofts and softs will also feature in China, but this time alongside the white-marked mediums.
Under rules established for 2016, teams have free choice between the three compounds at each race, within their allocation of 13 sets of tyres per Grand Prix.
They do however need to select at least one of each compound for Australia and China: in the former the ultrasoft is compulsory for Q3, while one of their the softs or supersofts must be used in the race; while in China, the supersoft is mandatory in Q3, and one set of either mediums or softs must be used during Sunday's race.
Pirelli's tyres will look markedly different for 2017, with the rear tyre width increased by roughly 25 percent - up from 325mm to 405mm. The width of the front tyres will also increase, from 245 to 305mm.
It is estimated that the new tyres, in addition to increased downforce levels, will produce cars that are between three and five seconds per lap faster than their 2016 counterparts.