What: Shares of Precision Castparts Corp. (PCP.DL) jumped 19% today after Warren Buffett's Berkshire Hathaway (BRK.A -0.27%) (BRK.B 0.01%) agreed to buy the company for $37 billion, including net debt.

So what: Berkshire Hathaway has offered to pay $235 per share in cash for Precision Castparts, which will become one of Buffett's largest subsidiaries once the deal is closed. Like many of Buffett's other businesses, Precision Castparts will remain a separately run company and will continue to be a major supplier to the aerospace industry, only now without some of the expectations that come with being a public company. 

Now what: Buffett has a long history of not only completing deals when he agrees to them, but also not increasing offers, so Precision Castparts shareholders don't have as much upside (or downside) as some other buyouts that have more risk in execution and potential for additional bids. With shares trading at nearly $231 today, there's also not a lot of upside for a deal that's expected to close in early 2016.

For Berkshire Hathaway, this is another big acquisition that will put cash to work and change the company's operations for the future. Having another manufacturing subsidiary with stable long-term cash flows and a competitive advantage in an industry like aerospace, which is tough for competitors to disrupt, should be great for shareholders long term. If anyone can make this a huge win despite the premium paid today, it's Warren Buffett.