Stocks to Watch: YHOO, CTAS, FLIR & More

Check out which companies are making headlines after the bell Monday:

Yahoo - The Internet company named former Google executive Marissa Mayer as its new president and CEO. Shares rallied in extended-hours trading. (Click here for after-hours quote.)

Cintas - The uniform maker posted earnings of 60 cents a share, in line with expectations, but reported sales of $1.05 billion, below expectations for $1.07 billion. In addition, the company handed in a 2013 full-year guidance that was at the lower-end of the expected range, pushing shares lower in extended-hours trading. (Click here for after-hours quote.)

FlirSystems - The thermal imaging systems manufacturer posted preliminary earnings of 30 cents a share, excluding one-time items, on revenue of $338 million, disappointing analysts who had expected earnings of 36 cents a share on sales of $380 million. In addition, the company handed in a weaker-than-expected full-year outlook, citing weakness in Europe. Shares fell in extended-hours trading. Flir will release its full results on July 26. (Click here for after-hours quote.)

Mattress Firm - The mattress retailer provided an updated full-year revenue guidance of between $1.01 billion and $1.03 billion, falling short of expectations for $1.04 billion. Shares plunged in extended-hours trading. (Click here for after-hours quote.)

JBHunt - The trucking and transportation company posted earnings of 67 cents a share, in line with expectations. But revenue missed expectations, sending shares lower in extended-hours trading. (Click here for after-hours quote.)

Agilent - The electronics manufacturer said it will buy AT4 wireless' Test Systems Business, but financial details of the deal were not disclosed. The acquisition is expected to be completed by early August. Shares edged higher in extended-hours trading. (Click here for after-hours quote.)

Life Technologies - The biotech company acquired privately held genomics company Navigenics, but financial terms were not disclosed. Shares edged higher in extended-hours trading. (Click here for after-hours quote.)

—By CNBC’s JeeYeon Park (Follow JeeYeon on Twitter: @JeeYeonParkCNBC)

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