The initial order will encompass 410 vehicles, all of which will enter service by 2020. Eventually 775 new cars are needed to replace Bart's oldest trains, and boost capacity on the network in light of increasing ridership following extension of the network to San Jose in 2018.

The evaluation process encompassed eight criteria, with price given the greatest weight based on the degree to which the bid exceeded the 60% Buy American local content mandate. Bombardier's bid for an eventual order of 775 cars came in at $US 1.54bn, and an overall score of 79.7, which beat Alstom's $US 1.73bn bid which received a score of 73.22, and Hyundai Rotem's $US 2.79bn offer which was scored at 48.47.