As agreed with the FIA, F1 tyre supplier Pirelli will conduct 25 days of in-season testing this year to help with the development of its future products and compounds.
Only Mercedes, Ferrari and Red Bull were called upon for testing in 2016 as they were the only teams which had the resources to help with the Italian manufacturer's development work.
But this season, all teams have signed for various assigned dates spread across six circuits, Bahrain, Barcelona, Paul Ricard, Silverstone, Magny-Cours and Interlagos.
Teams will be allowed run 2017-spec cars obviously but with no updated parts, while each outfit must submit to the FIA in advance the chassis number, the power unit and its electronic settings as well the car's bodywork configuration.
GALLERY: All the pictures from Friday in Bahrain
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