TULSA, Okla. ( TheStreet) -- AZZ ( AZZ) agreed to buy North American Galvanizing & Coatings ( NGA) for $7.50 a share in cash, or a total of $125.6 million. The purchase price is a premium of about 42.6% over the price of North American Galvanizing shares over the last 30 days, the companies said in a statement Thursday. North American Galvanizing shares closed Wednesday at $5.56. The transaction is expected to close before the end of August. North American Galvanizing provides corrosion protection for iron and steel components. AZZ makes specialty electrical equipment and provides hot dip galvanizing services to the steel fabrication market. -- Reported by Joseph Woelfel in New York. Follow TheStreet.com on Twitter and become a fan on Facebook.