Red Bull and Ferrari are amongst the teams to have made several changes to parts on their cars ahead of the Emilia Romagna Grand Prix.
A Technical Delegate's Report released by the FIA confirms that Red Bull have replaced various parts on Max Verstappen's car in parc ferme on Saturday and Sunday.
These are listed as the LHS and RHS diffuser stay, RWD exhaust tailpipe, front brake friction material and parameters associated with the change of brake material.
Sergio Perez's RB18 has been fitted with a new RHS RWEP light, front RHS brake caliper spat seal and there has also been work on the front wing/nose assembly.
Over at Ferrari, the changes made to Charles Leclerc's car are the HP Bosch fuel pump, RHS exhaust pressure sensor pipe, RHS engine intake assembly and parameters associated with engine intake assembly.
The list of parts changed on Carlos Sainz's F1-75 is much longer, following the Spaniard's crash in Friday's qualifying session. Alterations have been made to aspects including the power steering assembly, gearbox assembly and both front and rear wing assembly.
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Extensive changes for other cars
Other teams to carry out changes to their cars include McLaren, Alpine, Haas and Aston Martin.
The car with the longest list of alterations is Valtteri Bottas' Alfa Romeo, with the Finn having spent all of Saturday's Free Practice 2 session in the garage.
His teammate, Zhou Guanyu, has also had several parts changed. The F1 rookie crashed out of the Sprint race, and will start the main Grand Prix from the pit lane after his team were found to have breached the regulations by working on the car under parc ferme conditions.
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