[AlainH]

74) Quantity and type of tyres :
a) During the Event no driver may use more than four sets of dry-weather tyres, four sets of wetweather
tyres and three sets of extreme-weather tyres.
If a driver change is made during an Event the tyres allocated to the original driver must be used by
the new driver.
From the four sets of dry-weather tyres each driver will be allocated two sets of differing specification
for use on the first day of practice.
For the purposes of the above a set of tyres will be deemed to comprise two front and two rear tyres
of the same specification.
Before 08.00 (or 07.00 during Events taking place in North America) on the second day of practice
each driver must nominate which specification of tyre he will use for the remainder of the Event.
However, if both free practice sessions on the first day of practice are declared wet this decision may
be deferred until 12.00 (or 11.00 during Events taking place in North America).
Unless the use of wet or extreme-weather tyres is necessary one of the remaining unused sets of
dry-weather tyres must be used for both of the qualifying sessions, all reconnaissance laps and the
entire race. Unless a precautionary tyre change is necessary for clear and genuine safety reasons,
only a punctured or damaged tyre may be changed during a race. No refuelling will be permitted
whilst a car is in the pits for the purposes of changing a tyre.

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g) Prior to the start of the first qualifying practice session, and subject to the requirements of Articles
117 and 119, wet and extreme-weather tyres may only be used after the track has been declared wet
by the race director, following which extreme, wet or dry-weather tyres may be used for the remainder
of the relevant session.