The most attention-grabbing technical innovation on Russian Grand Prix practice day was one that won't be appearing in a Formula 1 race this year - or possibly ever.
We had already seen Mercedes' halo concept for cockpit protection run on the Ferrari in testing, and at Sochi on Friday Red Bull's high-strength aeroscreen proposal was finally revealed in physical form after CAD renders were issued last month.
The push for increased head protection for drivers is not a direct response to the crash that led to the death of Jules Bianchi, and no one in F1 is arguing that the proposals so far would have saved the Frenchman's life in that particular impact.