Mark XV or Mark 15 often refers to the 15th version of a product, frequently military hardware. "Mark", meaning "model" or "variant", can be abbreviated "Mk."
Mark XV or Mark 15 may refer to:
Technology Mark 15 torpedo, 1930 US Navy weapon plagued with development problems in World War II Supermarine Spitfire XV; a designation reserved for use with the Supermarine Seafire Mark 15 nuclear bomb; 1950s American thermonuclear bomb Mark 15 Phalanx CIWS; automated anti-missile gatling gun, entered US Navy service in 1980 Mark 15, a variant of the 8-inch/55-caliber gun MK 15, the US military designation for the McMillan TAC-50 Mark 15, British military term for an improvised mortar used by the Provisional IRA known as the Barrack buster
Other uses Mark 15 and Mark XV, the fifteenth chapter of the Gospel of Mark in the New Testament of the Christian Bible International Watch Company Mark XV; pilot watch produced from 1999 to 2006