Facebook kicks off its highly anticipated IPO road show Monday, but two men who won't be taking the pitch -- legendary investor Warren Buffett and his 88-year old co-pilot Charlie Munger.

Despite the hype, Buffett and Munger aren't interested in investing in Facebook for Berkshire Hathaway's portfolio or for their own, CNNMoney reports.

We never buy into an offering, Buffett told CNN at Berkshire's annual meeting in Omaha, Neb.

The idea that something coming out ... that's being offered with significant commissions, all kinds of publicity, the seller electing the time to sell, is going to be the best single investment that I can make in the world among thousands of choices is mathematically impossible, said Buffett.

I don't invest in what I don't understand. And I don't want to understand Facebook, Munger said. I don't want people putting all this personal stuff into a permanent record when they are 15 years of age. I think it's counterproductive. I just basically don't like it.

Still, Buffett wouldn't bet against Facebook -- or other leading techs. I would not short Facebook, I would not short Google, I would not short Apple -- they're fantastic companies. But in terms of what they'll be worth five or ten years from now, I just don't know.