The tyre company will bring two compounds of dry tyre to every venue .
Each driver must use both the ' option ' and ' prime ' compound over the course of each race , unless tyre company rains , and the wet or intermediate tyres are required .
The tyre company will bring two compounds of dry tyre to every venue , and each driver must use both the ' option ' and ' prime ' compound over the course of each race , unless it rains , and the wet or intermediate tyres are required .