Only three cars will be fitted with Kinetic Energy Recovery Systems (KERS) for the rest of the Chinese Grand Prix after Renault and BMW Sauber's Robert Kubica abandoned using the technology after evaluation in Friday practice.
Ferrari, BMW Sauber, McLaren and Renault had all used it in the first two races of the season, but it has become clear that the devices in their current state provide more of a strategic advantage than an ultimate performance benefit in terms of lap time.
Following reliability problems in Malaysia, Ferrari announced before the start of the Shanghai weekend that it was to not use KERS for the Chinese Grand Prix.
Now Renault, which only ran it in Nelson Piquet's machine in Friday practice, has decided to remove the technology completely as well.
Furthermore, Robert Kubica was not able to overcome tyre degradation issues caused by the extra weight of KERS when he tried it out in Friday practice, so he will not use it either.
With the weight of KERS causing knock-on implications to tyre wear, the challenge of looking after the rubber chosen for the Shanghai weekend has probably played a key role in the decision by teams to shy away from using it this time out.
It means that only McLaren duo Lewis Hamilton and Heikki Kovalainen, plus BMW Sauber's Nick Heidfeld, will run with KERS in Shanghai.