This is one of my favorite postcards because it shows one of my favorite beers, Kwak.
Bosteels Brewery is a beer brewery in Buggenhout, Belgium. The brewery was founded in 1791 and is still owned and operated by the same family, now its seventh generation. They brew three beers: Tripel Karmeliet, DeuS, and Pauwel Kwak.
Pauwel Kwak is an amber brewed since the 1980s with 8.4% ABV. Supposedly it is named after an 18th century innkeeper and brewer, Pauwel Kwak. The beer is filtered before packaging in bottles and kegs.
As with other Belgian beers, Kwak has a branded glass with its own distinctive shape. It is held upright in a wooden stand; the brewery claims the glass was designed by the innkeeper Pauwel Kwak in the early 19th century for coachmen who would stop at his coaching tavern and brewery named "De Hoorn". though the beer and the glass were launched in the 1980s. While drinking from the glass, the bulb at the bottom will remain filled for a relatively long time. As soon as air reaches the still-filled bulb, a large amount of beer will gush towards the drinker. This is accompanied by a characteristic sound which sounds like Kwak spoken quickly. [wikipedia]