Like the Domino Sugars sign, the Old Bay logo or the Oriole Bird, Mr. Boh has carved a spot in the pantheon of Baltimore icons.

The dapper, one-eyed mascot of National Bohemian beer smiles at the city from beer cans, T-shirts, tattoos — and a 27-foot-tall by 30-foot-wide sign atop the former National Brewing Co. complex in Brewers Hill. For 18 years, he winked at Baltimore, too.

When the Mr. Boh sign was installed in 2004, the mascot’s eye was outlined in red neon and timed to wink every few seconds. The steady gesture became a soothing fixture on the Southeast Baltimore skyline.

So when the neon burned out and Boh stopped winking in 2022, Baltimoreans took note.

“I was getting messages about it all the time,” said Nitasha Chopra, who took over as brand manager for National Bohemian shortly after the sign burned out.

Next week, Mr. Boh will finally wink again. The eye-conic sign is set to be relit — this time by LED lights instead of neon — on Sept. 25 at 7:30 p.m.

The return of the wink is the result of collaboration between the beer brand and Obrecht Commercial Real Estate, the building’s landlord. The complex, where National Bohemian was brewed until 1978, has since been converted to office space.

Chopra said they decided to use LED lights rather than neon for environmental reasons — neon lights use more energy — as well as practical ones. While neon can cost thousands of dollars to service and maintain, LED bulbs are easily replaced and offer the possibility of lighting Mr. Boh in other colors (Chopra envisions orange lights during baseball season, purple to cheer on the Ravens, green for St. Patrick’s Day and rainbow lighting for Pride Month.)

Domino Sugar similarly made the switch from neon to LED in 2021 for its massive sign overlooking the Inner Harbor, also citing durability and sustainability.

The update comes as Natty Boh makes a renewed marketing push ahead of its 140th birthday next year. The beer returned to Oriole Park at Camden Yards menus this season after an eight-year absence, and has been plugging partnerships with local watch company Tsao Baltimore and food influencer Bob’s Pizza Tour.

Though Natty Boh is now brewed in Latrobe, Pennsylvania, more than 75% of its sales are made within Maryland, Chopra said. Concern over Mr. Boh’s missing wink drove home the affection the city still has for the beer.

“The outpouring of concern from people in Baltimore was very endearing,” she said. “The sign is more than a sign; it’s part of Charm City. It’s part of Baltimore’s roots.”