When I last looked at diversified manufacturer Eaton Corp (NYSE:ETN) six months ago, I encouraged Fools to take the long view with this stock. The company had just "beat earnings" for the quarter, grown sales 18% year over year in the first half of 2005, and grown its profits per diluted share by twice that amount.

Three months later, fellow Fool W.D. Crotty took a look at the company and also liked what he saw: 10% sales growth, nearly double that increase in net profits, and -- get this -- back-to-back hikes in earnings guidance for the year. "Which year," you ask? Why, the one that Eaton will be reporting on before market-open on Monday, of course.

Thus, at last report, Eaton was projecting about $5.15 per diluted share in profit for fiscal 2005. So why, one wonders, are analysts projecting that the company will report $5.32 in profits per share on Monday? The answer is not likely tied to analysts believing Eaton will beat its own guidance (it's only surpassed analyst estimates twice in the past four quarters, and by minimal margins). Rather, I suspect the numbers that analysts are quoting, as reflected on Yahoo! Finance, refer to the company's operating earnings. For those, Eaton projected $5.25 to $5.35 per share for the year -- comfortably bookending the numbers that analysts are bandying about.

Then again, I don't think there's any need for Eaton to beat guidance, whether its own or anyone else's, for this company to make for a superior investment. Guidance numbers change from month to month. But one thing that hasn't changed in quite some time is Eaton's superb performance as a business.

You can get a sense of how well this company is chugging along, despite a pretty awful environment for the vehicle manufacturing industry that it services, by examining its margins. Just take a look at the beautiful line they're forming, as reflected in consecutive margin improvement over trailing-12-month periods for the past 18 months:

Margins

6/04

9/04

12/04

3/05

6/05

9/05

Gross

28.1%

28.2%

28.3%

28.3%

28.3%

28.4%

Op.

9%

9.2%

9.5%

9.6%

9.8%

10%

Net

5.9%

6.2%

6.6%

6.9%

7%

7.1%

All data courtesy of Capital IQ, a division of Standard & Poor's. Data reflects trailing 12 months performance for the quarters ending in the named months.

In each case, as you read left to right, the numbers just get bigger and bigger. Meanwhile, Eaton's share price has sat fairly still for the past 52 weeks. Does that sound like an opportunity to you? It does to me.

Fool contributor Rich Smith does not own shares in Eaton.