Pirelli will make their new, purple-marked ultrasoft tyre available in Canada - the first time the new compound will be used in a Grand Prix.
Alongside the ultrasoft tyre, teams will also be able to use the yellow-marked soft and red-marked supersoft tyre in Montreal, under the new-for-2016 tyre regulations.
As part of the new rules, in Canada every team must save at least one set of the ultrasoft for Q3. Those who qualify inside the top ten will have to give the tyre back to Pirelli at the end of qualifying, while those who do not make the cut can carry the extra set into the race.
Teams must also have at least two sets of softs in reserve for the race, and must use at least one of them.
Teams are free to choose the remaining allocation of their tyres to take them up to the mandatory total of 13 sets for the weekend.
The ultrasoft compound was used by some teams during the opening four-day test in Barcelona last week, with Red Bull's Daniel Ricciardo saying it "felt like another step on top of the supersoft - it was consistent and you can expect just a little bit more grip from it".
Early analysis suggested the tyre is around 0.5-0.8s per lap faster than the supersoft.
