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A former commercial fisherman widely credited with inventing the neoprene wetsuit. The attribution is incorrect—most historians now believe California physicist Hugh Bradner came up with it. (See Wetsuit.) But no one did a better job of making the wetsuit cool than Denver native O’Neill, a water-loving businessman who opened his first surf shop near San Francisco in 1952. O’Neill offered essential additions, including a stretchy nylon laminated onto the neoprene. More crucially, he popularized the image of the wetsuit-clad surfer, including one memorable ad that read “It’s Always Summer on the Inside” and featured a topless woman pulling on one of his suits. “He was a bearded one-eyed NorCal Don Draper,” says Matt Warshaw, author of The Encyclopedia of Surfing.