Pirelli aren't taking chances during the 2017 season and have therefore prepared back-up compounds should the all-new range fail to meet the requirements of the new 2017 cars.
Although Pirelli has tested its new, larger tyres on mule cars provided by Ferrari, Mercedes and Red Bull, the Italian company has still had to make a guess of what to expect as the mule cars aren't reaching the levels of downforce expected of this year's challengers.
The new compounds "make use of entirely new materials and a completely fresh design philosophy", according to Pirelli, therefore the supplier has developed a back-up tyre for each compound using more traditional methods should problems arise, such as the level of downforce proving far greater than their simulations suggested.
"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," Pirelli noted. "These extra compounds are formulated using more traditional criteria compared to the new base compounds.
"The back-up compounds could be introduced later in the season to respond to any particular requirements once the real performance levels of the 2017 cars have been identified."
