Shake Shack, the Manhattan-based burger chain founded by Danny Meyer in 2004, is poised to hit a major milestone next week. The company will open their 100th location at Boston's Seaport on Tuesday, August 16th, and to celebrate the occasion they're giving away many, many free meals.

Starting at 10:30 a.m. Tuesday, every standalone Shake Shack location will serve up 100 free single-patty ShackBurgers while supplies last. Only stadium and ballpark locations will be exempt from the hamburger free-for-all, which means that you're going to definitely want to check their list of NYC locations and plan for an early lunch (or late breakfast?) break on Tuesday to grab one of the best burgers the five boroughs has to offer.

"From our first-ever Shack in Madison Square Park twelve years ago, to so many incredible places in between, opening our 100th Shack at Boston Seaport is an epic milestone for us," Randy Garutti, CEO of Shake Shack, said in a statement Friday. CNBC reports the burger chain is working to boost sales after a weaker-than-expected same-store sales report was released last week. Following the poor financial status update, Shake Shack stock fell 8 percent.