Surveillance video captured a man grabbing the hat off the victim's head.
It happened Friday at Wallabout Street and Marcy Avenue in Williamsburg at 6:15 p.m.
The 27-year-old man was not hurt.
The traditional fur hat called a Shtreimel is worth $8,000.
The individual being sought is described as a man, 5'07" to 5'10" tall, 125lbs, and was wearing a hooded sweatshirt and gray sweatpants.
Anyone with information in regard to this incident is asked to call the NYPD's Crime Stoppers Hotline at 1-800-577-TIPS (8477) or for Spanish, 1-888-57-PISTA (74782).
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