The Longines Master Collection Date 40 is a classical wristwatch with a round case and automatic movement from Longines' popular Master Collection. Available in a number of versions, the present reference L2.793.4.51.6 has a Black dial. It is listed here with caliber L888.3, though depending on the year of production it can be powered by either the L619 or the L888 (-2 since 2017, -3 since 2019).