From the Facebook event page:

“Dogfish Head Brewery and Shinesty are bringing the tropics to GABF. Bring your favorite Hawaiian shirt and dance your pineapple off on LED dance floor.

Get free Dogfish and Shinesty swag. Win one of Dogfish Head's custom made Hawaiian shirts from Shinesty.

Cool down with a limited edition and one time only release of Dogfish Head SeaQuench Mango Margarita.

6 Dogfish Head beers on tap: 60 Minute IPA, SeaQuench Ale, Slightly Mighty, Punkin Ale, World Wide Stout, and Namaste White

Deets:
10pm-close
DJ D'Vinyl from Something Vinyl Club from 10pm-1am

Don't miss the best GABF party of the year!”