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OTRC: Michael J. Fox debuts 'Back To the Future 2' sneakers, weighs in on Charlie Sheen

Michael J. Fox appears in on the 'Late Show with David Letterman' on September 8, 2011. (CBS)

Michael J. Fox visited the "Late Show With David Letterman" on Thursday night to introduce the "Back to the Future- Part II"-inspired Nike Mags and the veteran actor also chimed in on the Charlie Sheen debate.

Sheen took over his role on "Spin City," which Fox also produced. Fox joked on the talk show: "It was especially good, because he worked and I got paid."

Sheen is gearing up for his Comedy Central Roast on Saturday, which will air on September 19th at 10 p.m. ET, but Fox had only kind words for the troubled former "Two and a Half Men" actor.

"He says he's doing okay, so who's it for me to say he's not?" Fox said. "That's a straightforward argument to me. He's winning, and that's fine, and I have no judgment about that... I wish Charlie all the best, and I wish Ashton all the best."

Fox compared the actor to his "Back to the Future" co-star Crispin Glover, who famously tried to take a shot at Letterman, "Any level of craziness, to me, hasn't risen to the level of Crispin Glover almost kicking you in the head... Crispin's not necessarily crazy either; he's just 'excitable.'"

Fox relented that those who go into show business tend to be on a different level, "We're all here, because we're not all there."

The actor visited the show to introduce a limited collection of sneakers similar to those worn by Michael J. Fox's character Marty McFly in the 1989 film "Back To The Future - Part II" called the Nike Mag. The first pair sold for $37,500, during a live auction hosted by "Community" actor Joel McHale on Thursday evening.

Nike said in a statement obtained by OnTheRedCarpet.com that it will auction off 1,500 pairs of the 2011 Nike Mag shoes on eBay, beginning on Thursday, September 8, at 5:30 p.m. ET. Proceeds are set to go to the Michael J. Fox Foundation, a charity that promotes efforts to find a cure for Parkinson's disease, an ailment the 50-year-old actor has suffered from for at least 20 years.

"This brings together three populations of people with major Joneses," Fox told Letterman, "the sneaker heads, who love sneakers the Back to the Future people, who, believe me, are out of their minds... in a good way! Thank God for them. And also the people in the Parkinson's community who have an interest in research."

In the "Back To The Future" films, McFly and his friend, a scientist named Dr. Emmett "Doc" Brown, played by Christopher Lloyd, use a DeLorean car that functions as a time machine to travel through time to try and change events in their past and future. The final movie was released in 1990 and was set in the Wild West.

The second film is set in 2015 and features the sneakers, which are also referred to as Air Mags and lace themselves onto McFly's feet when he steps into them.

"The 2011 NIKE MAG shoe was designed to be a precise replica of the original from "Back to the Future II," Nike's statement said. "The aesthetic is an exact match, down to the contours of the upper, the glowing LED panel and the electroluminescent NIKE in the strap. The 2011 NIKE MAG illuminates with the pinch of the 'ear' of the high top, glowing for five hours per charge."

In the spring of 2009, Nike secured patents for the technology to produce the futuristic footwear, which would feature an automatic lacing system.

The company has not explained how a Nike Mag shoe is secured, it features four straps across the front and a larger one around its opening. One advertisement for the sneakers (watch below) hinted that power-lacing wouldn't be available until 2015.

The eBay auction of the Nike Mag shoes will run for 10 days and 150 pairs of the 2011 NIKE MAG shoes will be made available each day via eBay's Fashion Vault. Fox revealed on the "Late Show" that Google co-founder Sergey Brin will match up to $50 million of sales, which will go to the actor's Parkinson's research foundation.

Watch Michael J. Fox's appearance on the "Late Show" and an advertisement for the Nike Air Mags below.