The small cap view: Buy industrial stocks for '15

John Rogers, member of "Squawk Box's" inaugural Portfolio Challenge, believes the operations of three small-cap firms will set them apart in a strong U.S. economy.

"We're bottom-up analysts that focus on the long-term fundamentals of the business," the chairman, CEO and CIO of Ariel Investments said. "We think industrial energy activity in the U.S. is generally strong, and will generally be helped by falling energy."

Here are his top picks: