EB3979
The 12 Duos were presumably intended for two basset horns. The autograph bears the heading "Di Wolfgang Amadé Mozart mp. Wien den 27t Jullius 1786 untern Kegelschieben" [… while playing skittles], which gave the duets - masterpieces of their kind - the name "Kegel-Duette" [Skittles Duets].