According to an Associated Press report (h/t ESPN), Lelands.com announced the sale Sunday. Robertson's ring came as part of the Milwaukee Bucks' 1971 title team, and the website will also be auctioning off a number of other items—highlighted by game-worn uniforms, his Hall of Fame ring and 11 of his All-Star rings.
Robertson's induction trophy from the Hall of Fame is also included. There are a total of 51 items in all.
Robertson, 79, was given the NBA's Lifetime Achievement Award last month. He and Russell Westbrook are the only players in NBA history to average a triple-double across an entire season, and he made 12 All-Star Games throughout his career while also being known as a pioneer for the sport.