The Scania 4-series low floor city bus and coach range was introduced by Scania in 1997 as a successor to the 3-series bus range. The 4-series bus range was first presented in September 1996, when the integral low-floor city bus OmniCity was revealed. Production of the chassis range started in second half of 1997, and by the end of 1998 all worldwide production facilities had changed from 3-series to 4-series. Unlike the 3-series, which was a range of 45 different chassis models, the 4-series is one basic chassis with different modular configurations depending on usage and customer needs. At launch there were a total of seven major configurations, presumably the F HB, K EB, K IB, L IB, L UB, N UA and N UB. These were later followed by the F HA, K UB, L IA, L UA and N UD. The first letter d