The vessel is an Offshore Subsea Construction Vessel (OSCV) designed and equipped for subsea operation duties such as construction and installation work, inspection and maintenance. The design is of type OSCV 11L. The vessel is environmentallly friendly with focus on low fuel consumption through its hull shape and diesel electric machinery. Siem Day is a vessel equipped with a 250 t active heave compensated subsea crane, capable of delivering loads to depths up to 3000 meters and is a versatile and cost effective working platform for a broad range of demanding offshore projects.