The effects on Cooper Lighting’s plant on U.S. 61 South remain unclear after an $11.8 billion merger became final on Oct. 26.

Shareholders of Cooper Industries and Eaton Corp. approved Eaton’s merger announced in May.

Of 68 percent of Cooper’s outstanding shares voted, 99.45 percent favored the deal, according to a jointly issued release after separate meetings were held Oct. 26 in each firm’s respective U.S. headquarters. About 78 percent of Eaton’s shareholders approved the merger, it said.

Eaton will control 73 percent of the new company, to be called Eaton Corporation PLC and based in Ireland, though Eaton will retain its administrative headquarters in Ohio. The deal is subject to closing conditions and regulatory clearances.

Cooper employs nearly 26,000 worldwide and produces lighting systems, circuit protectors, wiring devices and power distribution and transmission systems. Its operations in the United States are based in Houston. Its Vicksburg plant opened in 1987 and has an annual payroll of about $12 million.

Eaton makes electrical and hydraulic components, aerospace fueling and pneumatic systems for the military and vehicle drivetrain and powertrain systems.

The deal’s impact on jobs or product lines at the Vicksburg plant won’t be known until after the deal closes, said Ken Mathis, plant manager at Cooper Lighting in Vicksburg.

“We don’t know anything definite,” Mathis said. “We do know Eaton doesn’t have the same products we do.”

The merger will create a “premier global power management company,” read part of the release issued after the shareholders’ vote.

“Our strong, complementary product offerings provide expanded opportunities to accelerate our global growth by addressing our customers’ most complex electrical requirements,” Eaton chairman and CEO Alexander Cutler said in the release.

In 2011, Eaton reported $16 billion in revenues. Cooper claimed $5.4 billion for the year, with 40 percent of total sales to customers outside the U.S.