Nike Skate Boarding, primarily known as Nike SB, is the Nike brand for its line of shoes, clothing, and equipment for skate boarding.
The most noticeable difference between the two sneakers are their tongues. On the Nike Dunk, you get a slim, mesh tongue. On the SB Dunk, the tongue has been beefed up to provide more cushion and protection. By being thicker, the tongue helps with the fit as well.