SM53, originally designed MBO and colloquially known as Høka, were a class of 58 trams and 50 trailers built by Høka and Hägglund for Oslo Sporveier. Part of the Hägglund Mustang family, the units were used on the Norway's Oslo Tramway from 1952 until 2000. The 14.7-meter (48 ft) long and 2.5-meter (8 ft 2 in) wide trams weighed 16.9 tonnes (16.6 long tons; 18.6 short tons).