Image source: Oshkosh Corp. What: Shares of equipment manufacturer Oshkosh Corp. (NYSE: OSK) jumped 15.5% in July after the company reported better-than-expected earnings results. So what: Revenue for the fiscal third quarter was up 8.4% to $1.75 billion, but net income was down 6.1% to $84.2 million, or $1.13 per share. Defense as well as fire and emergency were the highlights, with revenue rising 36.1% for defense and 24.4% for fire and emergency, and both showing a sharp rise in operating income. For the full year, management now expects sales of $6.0 billion-$6.1 billion, up from previous guidance of $5.7 billion-$6.0 billion, and earnings per share of $2.60-$2.80, up from $2.30-$2.70 previously. Now what: The quarterly results were impressive, but the guidance update is what should really catch investors' attention. It shows a longer-term improvement in the company's revenue and bottom line, and indicates that the pop in the defense and fire and emergency segments won't be short-lived. Shares aren't cheap at 20 times the top end of full-year earnings estimates, but if the performance continues, this could be a nice defense play for investors. A secret billion-dollar stock opportunity The world's biggest tech company forgot to show you something, but a few Wall Street analysts and the Fool didn't miss a beat: There's a small company that's powering their brand-new gadgets and the coming revolution in technology. And we think its stock price has nearly unlimited room to run for early in-the-know investors! To be one of them, just click here.Travis Hoium has no position in any stocks mentioned. The Motley Fool has no position in any of the stocks mentioned. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.