Formula One's official safety and medical cars will be provided by both Aston Martin and Mercedes at different events this season, the governing body FIA confirmed on Monday.
Mercedes had been sole supplier of both cars since 1996, but the sharing arrangement was flagged up last year.
Aston Martin are returning as a constructor this season for the first time in 60 years with the rebranded Racing Point team, owned by Canadian billionaire Lawrence Stroll.
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The Mercedes-AMG GTR and C63S cars will have a new red livery while the Aston Martin Vantage and DBX cars, to debut at the Bahrain season-opener on March 28, will be green.
Germany's Bernd Maylander and South African Alan van der Merwe will remain safety and medical car drivers respectively.
The Mercedes cars will be used at the second race at Imola in Italy and the two carmakers will split the remainder of the season.
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