In a video posted to Twitter, a Florida man wearing a "Running the World Since 1776" shirt flips out on a fellow Costco shopper who asked him to wear a mask.

• RawStory noted that the shopper is identified on social media as an elderly woman, who can be heard telling the man to “Stay six feet away from me.”
• He says to the woman, “You’re harassing me and my family,” before the audio temporarily cuts out and then he advances toward the woman.
• “I feel threatened,” the man yells, clenching his fists. “Back up. Threaten me again.”

A girl can be heard in the background trying to calm her father, who halts his advance before turning back to bellow once more.

“Back the f*ck up,” he screams, clenching his fists and advancing toward the shopper again. “Put your f*cking phone down.”

He eventually walks away.

Watch.