Break out your coffee pots, pitchers, and super-size thermoses: Today and tomorrow, NBC4 Washington reports, 7-Eleven wants you to beat the summer heat with a huge, $1.50 Slurpee, served in the drinking vessel of your choice.

Since 2015, fans of the chain’s frosty, sugar-laden beverages have waited with bated breath (oversized container in hand) for Slurpee's annual Bring Your Own Cup Day. The special, limited-time promotion—which as the name indicates, lets you fill any giant cup for an exceedingly low price—launched in 2015, and (so far) typically occurs once a year.

The last BYOC Day ran from March 18 to March 19 (contrary to its name, the event always lasts two days). Now, as part of its year-long 50th anniversary celebration, 7-Eleven has brought back the popular occasion for a second time, from August 19 to 20. 

The promotion runs from 11 a.m. to 7 p.m. (no late night snack runs!), and there are a few rules: Containers "must fit upright through a 10-inch hole”—in other words, you can’t bring in, say, a two-gallon fish tank—and for health and safety purposes, it must be clean and leak-free, among other stipulations.

Regulations aside, feel free to have fun—and even get a little weird—with the quirky micro-holiday. “We saw just how creative Slurpee fans can get during the first BYOCupDay,” Laura Gordon, 7-Eleven's vice president of marketing and brand innovation, said in a statement. “They filled drums, kettles, fishbowls, helmets, and teapots."

Still have questions (or wondering if that giant margarita glass makes the cut)? Visit Slurpee’s website for more info.

[h/t NBC Washington]

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