What are the men in this photo wearing?

The people in the picture are gathered and dressed-up in the same manner not accidentally. All of them are the participants of a leisure suit convention, a special event for the lovers of retro fashion.

Leisure suits first appeared on the American west coast at the end of 1930s and became extremely popular among the wealthy. It was a comfortable summer casual-wear made from lightweight fabric, which became a common formal-wear in 1950s. Leisure suits, also called "Hollywood suits", often featured contrasting yokes, collars and cuffs. Many musicians and actors wore them, such as Elvis Presley and Tex Williams. The leisure suit height of popularity was around the mid to late 1970s, but fell from fashion in the very early 1980s. The leisure suit became associated in popular culture with bars, gangsterism, and, conversely, with clueless dressing.