U.S.-listed power management company Eaton Corporation is in advanced talks to buy Turkey's Ulusoy Elektrik for around $300 million, two sources with knowledge of the deal told Reuters on Wednesday.

The transaction would see Eaton acquire more than 80 percent of the switchgear maker from members of the founding Ulusoy family, and launch a tender offer to minority shareholders for the remaining stake, the sources said.

A representative for Eaton, which is listed on the New York Stock Exchange (NYSE) and headquartered in Dublin, Ireland, declined to comment, as did a representative for Ulusoy.

The deal is expected to be signed in the coming days and follows several months of negotiations, the sources said.

"The value of the deal is around $300 million," one of the sources said. The sources declined to be identified because the information had not yet been made public.

Shares in Ulusoy, which had been up nearly 5 percent on the day before the news, extended gains. They were up nearly 11.77 percent over TL 17 at 10:32 by local time.

Ulusoy Elektrik, which makes switchgears used in power distribution systems and the overhead line equipment used in railways, has production facilities in Turkey, Indonesia and Algeria. It recorded a net profit of 51.3 million lira ($10 million) and an EBITDA margin of 30.7 percent in the third quarter, according to its website. In 2012, Eaton Corp. acquired Turkish hydraulic and industrial hose manufacturer Polimer Kauçuk for an undisclosed amount.