Peach bitters
From The Webtender Wiki
Peach bitters is a type of cocktail bitters that was popular in the decades before Prohibition. But afterwards, this product practically disappeared from the global market.
The only two commercial manufacturers of peach bitters at the moment are Fee Brothers and The Bitter Truth. Fee Brothers' Peach Bitters is sweeter and does not contain alcohol; The Bitter Truth bitters is more complex in flavor and contains alcohol.
This ingredient is a component of the Xeres Cocktail.