July 18 (Reuters) - Cyber-security startup StackRox said on Tuesday it has raised $14 million in a Series A funding round led by Sequoia Capital, providing the three-year old company with funds to use for product development and expansion of its sales team.

The Mountain View, California-based company also unveiled its first product: software for securing the contents of "containers," which are stacks of software that make it more efficient to run multiple applications on top of a single operating system.

Chief Executive Sameer Bhalotra told Reuters that the company has several paying customers, including firms in the finance, media and technology industries as well as the U.S. federal government.

Bhalotra, former White House senior director for cyber security under former U.S. President Barack Obama, declined to say how many customers are using the software.

(Reporting by Jim Finkle in Toronto; editing by Diane Craft)