Mozart's Flute Quartet No.1 in D Major, K. 285 is written for flute, violin, viola and cello. It is the first of three quartets written in Mannheim, Germany at the request of Ferdinand De Jean who was introduced to Mozart by Christian Cannabich. Mozart first mentioned his quartets in a letter to his father, Leopold Mozart on December 10, 1777,[1] and the first quartet is dated December 25, 1777.[2]