a B-series unit weighs . The trains have a steel body and the entire cabin is pressurized. Rail brakes are installed on all carrying bogies. The A-series has a capacity of 207 seated passengers, while the B-series has room for 250. The difference is due to the B-series having a smaller bistro and more compact seating. In the A-series, each of the four cars has seating in a different color (blue in BFM73 car, green in BMU73, red in BFR73, and yellow leather in BM73 and in the bistro area in BFR73). Originally, three of the cars had floors with carpet, while the fourth car (BFM73) had vinyl, of consideration to people with allergies. The carpets were removed in about 2005 as it was difficult to keep them clean. Seating is in two classes, standard and Komfort (originally "Plus"); the latter (BM73 car) with leather seating and power supply for laptops. All the cars have cherry tree wood interior. The trains are equipped with a dining section (BFR73 car) and warm meals can be served at the seat or in the diner. The menu is according to the time of day, with breakfasts in the morning and larger meals in the afternoon and evening. The trains also feature a family section with a play area and HC area (BFM73 car). The BFM73 car has also a bicycle room behind the driver's cab. From 2011, the trains are equipped with free wireless Internet. History Background In 1990 and 1994, NSB published two reports regarding the future of intercity rail transport in Norway. The reports concluded that there would have to be invested 56 billion Norwegian krone (NOK) in new infrastructure if the main corridors were to be built as high-speed railways. Instead, the use of tilting technology was proposed to allow higher speeds on existing lines. In 1992, the Parliament of Norway voted to build Oslo Airport, Gardermoen and connect it to the capital with the high-speed Gardermoen Line. It was decided that the service should take 19 minutes—and not one minute more. When issuing invitations to tenders, NSB specified this time limit as a criterion, which was also the reason the line was dimensioned for . Proposals had been made for NSB to purchase the same units as the Swedish State Railways (SJ), the X2, in a Nordic cooperation to use the same trains in Norway, Sweden and Denmark, but