If you, like many American men, work in an office, you should know that there are things you simply should not wear.

And yet, we see them all the time anyway.

So Business Insider figured it was time to put some of the obvious transgressions onto one definitive list of things no man should wear to the office.

Some of these things look sloppy, some of them look childish, and some of them look just plain ridiculous.

None of that is anything you want.

And since we know you’re wondering, yes all these rules still apply on casual Friday. It’s called “casual” Friday, not “dress like you’re at your best buddy’s house” Friday.

Shouts to Jessica Cadmus of The Wardrobe Whisperer for helping us cobble this eyesore together.

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