Maybe Mondays aren’t that bad — distract yourself from midterms with a free sweet treat from Shake Shack! GrubHub and Shake Shack just announced a new offer, #FreeShakeMondays, where customers can receive a free Shake Shack milkshake with free delivery from GrubHub on every Monday for the rest of the month of March with any $15 purchase. 

The offer includes any and every flavor milkshake from Shake Shack’s menu, including their Chocolate Pie and Wake & Shake specialty shakes. The Chocolate Pie milkshake consists of chocolate ganache toasted oat pie from Four & Twenty Blackbirds, hand spun with chocolate frozen custard, topped with croissant cookie crumbles. The Wake & Shake offers a coffee-citrus ice cream combo, with Red Bay coffee hand spun with vanilla frozen custard, maple syrup, and orange zest, topped with whipped cream and orange candies

According to the terms of the deal, a $15 purchase is required through GrubHub, and all you have to do is add the milkshake of your choice to your order – it will automatically apply the discount, no coupon code required. The deal is available until March 28, the last Monday of the month, and has a limit of one milkshake per customer per day.

This fun partnership with GrubHub comes after Shake Shack’s past programs with their own dating app, Eat Cute, and a milkshake collaboration with MilkBar. In the meantime, spend those $15 on the burger chain’s new buffalo chicken sandwich, the vegetarian friendly Shroom burger, or get a bang for your buck with these menu hacks