Carlos Sainz Jr will race with the number 55
Named Toro Rosso driver for the 2015 season, Carlos Sainz Jr indicated that he would carry the number 55 for his career in F1.

Announced as a regular driver for the next season, alongside Max Verstappen, at Toro Rosso, Carlos Sainz Jr revealed that he would race with the number 55.
The 20-year-old Spaniard, champion of the Formula 3.5 of the World Series by Renault, will make his grand debut in 2015, replacing Jean-Eric Vergne. Like every driver since 2014, he must choose a number that will be his own for his entire F1 career.
During a press conference in Madrid, Sainz indicated that he would wear the number 55. Like Valtteri Bottas (Val77eri Bo77as), this number will actually symbolize the two letters “S” obtained when his first name and last name are joined together, as in the hashtag ‘#Carlo55ainz’.
Other drivers will have to choose their own number by the start of the season: Max Verstappen and Felipe Nasr, both future rookies in the premier category.