As early as 1909, the American Can Company had experimented with beverage cans, but none of the prototypes could withstand pressure from carbonation. In 1933, with Prohibition at an end, the company developed "keg-lining," a technique to coat the inside of beer cans in the same way that a keg was lined. Constructed from heavy gauge steel, these first beer cans required a special tool to punch a hole in their solid, flat tops. In the beginning, Krueger executives weren't very excited by the canned beer concept, but that view changed when American Can offered to install all the canning equipment gratis, freeing Krueger from any obligation if the product was not a success.
Canned beer was a hit right from the start, with a 91 percent approval rating. In the first week of production, 2,000 cans of Krueger's Finest Beer and Krueger's Cream Ale were delivered to fans of the brewery in Richmond. Soon other breweries copied the idea; cans were lighter and cheaper to manufacture than bottles. By the end of the year, 37 breweries were selling canned beer nationwide.
During World War II, canning of beverages declined, curtailed by conservation of metals for the war effort. Aluminum cans with pull tabs were introduced in 1958; they were lighter and even cheaper to produce. Today, canned beer accounts for about half of the $20 billion total yearly U.S. beer sales.