BALTIMORE (WJZ) — Perhaps the most iconic convenience store product ever, the Slurpee, turns 50 this year.

As a result, 7-Eleven is celebrating with “Bring Your Own Cup Day,” this Friday and Saturday from 11 a.m. to 7 p.m.

It’ll cost fans of the frozen treat just $1.50 to fill up (almost) any container they can imagine.

There are just a few rules you must comply to. Your “cup” must be food safe, watertight and must fit upright through a 10-inch hole.

Examples of acceptable containers provided on Slurpee.com include a fish bowl and a hollowed out pineapple.

Toasters and shoes, however, are frowned upon.

Get the idea?

Here are some photos of containers that some have used on #BYOCupDay in the past:

PSA// bring ya own cup day at 7/11 is on Friday and Saturday #byocupday pic.twitter.com/OO3lu5eiYX — wholesome meme (@Madelyn_pedia) August 16, 2016

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