Mercedes and Ferrari are among several teams to change car parts between qualifying and the race at the Miami Grand Prix.
Ferrari have fitted a new fuel primer pump to Charles Leclerc's car, while Mercedes have replaced the RHS (right-hand side) external master switch on George Russell's machine.
These parts have been replaced with the approval of FIA Technical Delegate Jo Bauer, following a written request from the teams.
Several changes up and down the F1 grid
In addition to Ferrari and Mercedes, various penalty-free changes have been made at McLaren, Alpine, AlphaTauri, Williams, Alfa Romeo and Haas.
The biggest list of modifications comes at Alpine, following Esteban Ocon's heavy crash during final practice, which ruled him out of qualifying.
Along with a host of new bodywork, the gearbox, survival cell, driver's seat and steering column/rack have been swapped out on Ocon's car.
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