Ein stein! But how long can you hold it?

Ein stein! But how long can you hold it?
Community Newspaper Group / Kate Briquelet

Show the world you can hold your beer!

Der Schwarze Kölner will host a mug-holding contest on Tuesday night to find Fort Greene’s strongest drinker — the first step towards becoming a national beer-mug-holding champion.

But the Bavarian sport isn’t just about the illustrious title.

“People make fun of themselves and their friends,” said Greta Acosta-Black, head beer wench at Der Schwarze Kölner. “No one takes it personally — because when you lose, you start drinking the consolation prize already in your hand!”

Contenders will engage in an epic battle of endurance as they raise a one-liter lager-filled glass mug — about five pounds — for as long as possible.

Sound easy? Here are the rules: The beer-holding arm must be held out straight, parallel to the ground and directly in front of the chest. If you spill a drop, you’re disqualified.

The name of the game is Masskrugstemmen, which translates loosely into “beer-mug lift”; this is the third year that the United States will host a national competition.

America’s reigning champion clocked in at 10 minutes 30 seconds, but the world record is an excruciating 19 minutes. The Brooklyn record, set last year at the Fulton Street biergarten, is four-and-a-half minutes — set by one of the bar’s employees, Rogelio Juarez.

“I never practiced,” said Juarez, 49. “It’s not about your hands — it’s all in your head.”

Tuesday’s winner will secure bragging rights, Das Boot — a two-liter glass beer boot — and a headshot on next year’s promotional poster.

The victor will head to Brooklyn’s run-off round on Aug. 30, before entering the national competition in Central Park on Sept. 17.

Der Schwarze Kölner [710 Fulton St. at Hanson Place in Fort Greene, (347) 841-4495], Aug. 23 at 8 pm. No registration is necessary, so just show up.