The growth areas are tightly defined; there exist pockets with soils atypical of the area producing eaux de vie that may have characteristics particular to their location. Hennessy usually uses the unofficial brandy grades for its cognac offerings, but has also produced three single distillery cognacs, each with very distinctive flavours arising from the different soils and, to a lesser extent, climate. Other cognac houses, such as Moyet, exclusively use the crus to describe their different cognacs.