and rally held in Downtown. Rolling stock METRO currently operates three generations of light rail vehicles. All of them are double-articulated, 70% low-floor vehicles with four low-platform doors per side to provide level boarding. H1 series The original fleet of 18 vehicles was built by Siemens Transportation Systems in Sacramento, California; the $117.9 million contract for Siemens included the light rail infrastructure (traction power, signals, and communication systems) and an initial order of 15 light rail vehicles. Three additional vehicles were ordered in 2002. 101 to 115 were delivered in 2003 and 116 to 118 in 2004, for the opening of the first stage of the Red Line. Designated by the manufacturer as S70 and based roughly on earlier vehicles built for Portland's MAX Light Rail system, each vehicle is long and has a top speed of . They have a capacity of 72 seated and approximately 169 standing passengers, or a total capacity of around 241 per car. This approximately 250-person capacity has been reached on certain Super Bowl weekends. The H1 series cars are distinguishable by their streamlined cab ends and rectangular headlamps, with the electronic destination sign (which have been modified to indicate the line with a colored square) mounted directly in front of the cab rather than above it. They are normally used only on the Red Line and can be operated as single cars or in trains of two cars coupled together, though two-car trains have become the norm due to increasing ridership and the arrival of the H2 series. H2 series For expansion of the METRORail system, METRO turned to CAF USA, with a total order of 105 cars placed in May 2010. A subsequent investigation by the Federal Transit Administration determined the procurement violated the Buy America Act, and the million order was cancelled in February 2011. CAF gave a partial refund of million, which METRO applied to the purchase of what would become the H2 series cars. In the spring of 2011, METRO purchased a further 19 Siemens S70 vehicles (the same model as its original 18), citing the need to accommodate ridership that was 4 years ahead of expectations and to get cars more quickly. These cars were options under a contract for Utah Transit Authority's TRAX system, which METRO purchased for $83 million after UTA decided not to exercise its options. As with the previous H1 generation, these new cars