The “Reference” series appears in two versions:- Reference 36- Reference 54.Each model has a specific tone colour: the “Reference 36” features a rich open tone, in the tradition of the “Balanced Action” manufactured early 1936. The more centred “Reference 54” integrates the famous “Mark VI” design, which was manufactured from 1954.Key: B-flat.Range: high F sharp.Thumb rest: adjustable, in metal.Leather pads, plastic booster.Finishe: DGG (dark gold lacquer, “Reference” engraving).Selmer Paris mouthpiece.“Reference” case.