Baku, March 11, AZERTAC

Pirelli has unveiled the tyre compound selections for Spain, Monaco, Canada and Baku.

F1's rules dictate that Pirelli brings three compounds to every grand prix weekend. Teams and drivers then select how many sets of each tyre they would like, with 13 allowed in total.

Pirelli will opt for the hardest tyres in its range for the Spanish Grand Prix, the first time we will see the hard tyre this season. Teams will have extensive data of Pirelli's new-for-2017 rubber from eight days of pre-season testing at the Circuit de Catalunya. The next two races, Monaco and Canada, see the return of the ultra-soft tyres, which will also feature at the season-opener in Australia and Russia.

Azerbaijan's street race will once again not feature the ultra-soft tyre. The street circuit joined the calendar last year but Pirelli opted against taking the purple-striped compound, which was introduced in 2016, to Baku due to a lack of data. For the second year in a row, perhaps because of the extensive changes to the tyres this year, teams will again use the medium, soft and super-soft tyre despite the ultra-soft being the preferred compound for street circuits.

In all four cases, the 'softest' tyre in the range is the one designated for qualifying (meaning it must be used by those who proceed to Q3). The two 'harder' compounds at each race are designated for the race, meaning teams must have at one set of each available come Sunday's race and use one at least one of them.