The X73900 is a Diesel Multiple Unit (DMU) train type operated by the SNCF in France. They were built from 2001 to 2004 by Alsthom DDF. They are a version of the SNCF Class X 73500 equipped with train control systems for transborder services to Germany. The trains are single railcars, and have been nicknamed Blue Whales (Baleines bleues) Cucumbers (Concombres) or Sausages (Saucisses). The units were ordered joint with Deutsche Bahn, with their Class 641 units. The trains have modern features which were new to TER trains, such as: The trains can work in multiple of up to 3 sets. They are numbered X 73901 - X73919. The units are used on services that operate into Germany from France. They operate the following services: The class is allocated to Strasbourg depot.