Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of copper-cable king Belden (NYSE: BDC) connected with investors today, jolting share prices up by as much as 12.2% overnight on above-average volume.

So what: Belden's second quarter crushed analyst estimates, amplified by a stronger outlook for the third quarter. Sales jumped 31% year-over-year to $536 million, including organic growth of 17% if you exclude currency exchange effects and recent acquisitions.

Now what: Before you write copper cables off as obsolete, killed by wireless communications or fiber-optics from Corning (NYSE: GLW) and others, consider that both Belden and chief competitor General Cable (NYSE: BGC) have destroyed Corning and the S&P 500 in the stock market over the last year. Belden's revenue growth speaks for itself, and the company claims to have only a 30% share of the domestic market even though it is the clear leader, leaving plenty of room for both organic share growth and more acquisitions. If you need a refresher on how to invest in underrated makers of networking equipment, just download this free report.

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