Both Sergio Perez and Zhou Guanyu are set to take Formula 1 grid penalties at the United States Grand Prix in Austin.
Red Bull driver Perez and Alfa Romeo's Zhou have had a fifth Internal Combustion Engine (ICE) fitted to their cars ahead of the weekend.
Drivers are only allowed three ICEs for the season, with both taking five-place grid drops.
Perez has also taken a seventh exhaust system aboard his RB18 machine, with World Champion teammate Max Verstappen following suit.
However, as both are allowed eight for the season, no penalty is forthcoming.
The Ferrari duo of Charles Leclerc and Carlos Sainz Jr are also set for the grid drop, but have not yet taken their fresh elements, with the team planning to take the new components on Saturday.
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