Legendary golfer Arnold Palmer, who passed away Sunday, Sept. 25, was as much known for the sport he made famous as he was for the myriad products he endorsed. Among them: An automatic pool cleaner.

In the late 1970s, his testimonials for the Arneson Pool Sweep graced the pages of in-flight magazines.

“I gave up my title for best pool cleaner years ago,” reads one ad inviting pool owners to join “Arnie’s Navy.” The ad continues: “It was no contest. My Arneson Pool Sweep cleans my pool better than I ever did.”

Inventor Howard Arneson said getting Palmer to put his weight behind the product was a “good move” for the company.

Palmer wasn’t just a spokesman for the Arneson Pool Sweep. He was a customer.

“He was very satisfied with it and loved it,” said Arneson, now retired.

Arneson met “The King,” as he was called, on a number of occasions and found him just as warm and charming as he presented himself on the green.

“He was just wonderful,” he said. “A perfect gentleman.”

Palmer may have had other pool-centric dealings. Correspondences between his agent, Mark McCormack, and Conkey Swimming Pool Supply in Foxboro, Mass., indicate that the parties were exploring business opportunities. (Side note: McCormack also represented Gary Player, another golf great whom McCormack said had “a rather extensive arrangement” with an outfit called Penguin Pools in South Africa.)

While the full extent of Palmer’s involvement in the industry is unknown, one thing is for certain: He did wonders for the Arneson Pool Sweep.

With the superstar’s backing, Arneson said the cleaner sold more than a million units.