much branding contributes to the concept of "super-premium vodkas". Distilling and filtering A common property of the vodkas produced in the United States and Europe is the extensive use of filtration before any additional processing including the addition of flavorants. Filtering is sometimes done in the still during distillation, as well as afterward, where the distilled vodka is filtered through activated charcoal and other media to absorb trace amounts of substances that alter or impart off-flavors to the vodka. However, this is not the case in the traditional vodka-producing nations, so many distillers from these countries prefer to use very accurate distillation but minimal filtering, thus preserving the unique flavors and characteristics of their products. The master distiller is in charge of distilling the vodka and directing its filtration, which includes the removal of the "fore-shots", "heads" and "tails". These components of the distillate contain flavor compounds such as ethyl acetate and ethyl lactate (heads) as well as the fusel oils (tails) that impact the usually desired clean taste of vodka. Through numerous rounds of distillation, or the use of a fractioning still, the taste is modified and clarity is increased. In contrast, the distillery process for liquors such as whiskey, rum, and baijiu allow portions of the "heads" and "tails" to remain, giving them their unique flavors. Repeated distillation of vodka will make its ethanol level much higher than is acceptable to most end users, whether legislation determines strength limits or not. Depending on the distillation method and the technique of the still master, the final filtered and distilled vodka may have as much as 95–96% ethanol. As such, most vodka is diluted with water before bottling. Flavoring While most vodkas are unflavored, many flavored vodkas have been produced in traditional vodka-drinking areas, often as home-made recipes to improve vodka's taste or for medicinal purposes. Flavorings include red pepper, ginger, fruit flavors, vanilla, chocolate (without sweetener), and cinnamon. In Russia, vodka flavored with honey and pepper, pertsovka in Russian, is also very popular. In Poland and Belarus, the leaves of the local bison grass are added to produce żubrówka (Polish) and zubrovka (Belarusian) vodka, with slightly sweet flavors and light amber colors. In Lithuania and Poland, a famous vodka containing honey is called krupnik. This tradition of flavoring is also prevalent in the Nordic countries, where vodka seasoned with herbs, fruits, and spices is the appropriate strong drink for