"You're supposed to feel safe and comfortable here, and for a letter like that to come from the administration is really appalling," Bri Burtop says

A Pennsylvania high school is under fire for what many are calling an offensive, sexist letter that instructed female students to hide their “sausage rolls” at graduation and keep “the girls” covered.

The backlash began when Biglerville High School senior Bri Burtop took issue with a letter sent home ahead of Friday’s ceremony.

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According to a copy of the notice obtained by an ABC News affiliate, “gentlemen” were warned to “PULL YOUR PANTS UP!” And while collared shirts were recommended, t-shirts would be allowed for guys – but females were asked to wear “a longer skirt” or “nice slacks” and “modest attire.”

“Here they say, ‘Choose modest attire, no bellies showing, keep “the girls” covered and supported’ – which really bothered me,” Burtop told ABC News. “It also says that they don’t want to be looking at our ‘sausage rolls’, and ‘as you get dressed remember that you can’t put 10 lbs. of mud in a 5 llb. bag.’ ”

“You’re supposed to feel safe and comfortable here, and for a letter like that to come from the administration is really appalling,” she added in another ABC interview.

Now Burtop and her mother are threatening to sue.

“You can’t talk to women like that in a work place. It’s just totally wrong, it’s totally degrading,” her mom Jessica said.

But high school officials insist the letter does not reflect their values.

“The Administration acknowledges that some individuals have found certain language in the document to be inappropriate or in poor taste,” the Upper Adams School District said in a statement. “The document was drafted years ago, and the author of the original document has since retired.”

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Not everyone is offended, though. A Biglerville alumna told Hanover, Pennsylvania’s The Evening Sun that the dress code is meant as a joke.