Pirelli has prepared a back-up tyre compound for 2017 in case it needs "to respond to any particular requirements" of next season's F1 cars.
New aerodynamic regulations in 2017 will be introduced in an attempt to make cars five seconds per lap faster. The new regulations also include wider tyres, giving Pirelli a challenge to ensure the rubber provides the required step forward in performance as well as being able to deal with the increased aerodynamic loads.
Having carried out numerous days of testing the wider tyres on mule cars supplied by Mercedes, Red Bull and Ferrari, Pirelli says it has developed a back-up set of compounds in case the 2017 cars are at a different performance level than expected.
"The compounds in particular make use of entirely new materials and a completely fresh design philosophy," Pirelli said in a statement. "After a very positive testing programme with the new sizes Pirelli has decided to additionally homologate a back-up compound alongside each of the five new base compounds.
"These extra compounds are formulated using more traditional criteria compared to the new base compounds. For the first part of the championship, only the new-generation base compounds have been selected.
"The back-up compounds could be introduced later during the course of next season to respond to any particular requirements once the real performance levels of the 2017 cars have been identified."