BOTHELL — A Massachusetts-based infrastructure security firm has acquired Teltone Corp., a local firm that has specialized in secure communications for the power industry.

Industrial Defender Inc., which did not disclose terms of its acquisition, said it plans to keep Teltone’s offices and nearly two dozen employees in Bothell. They will work under the Industrial Defender name.

“We absolutely find a lot of value and talent in that team,” Todd Nicholson, Industrial Defender’s chief marketing officer said of Teltone.

Nicholson said his company has worked with Teltone as a technology partner and the strengths of the two fit together well.

“When you look at the combination of experience and technology offerings, it’s a win-win” for Industrial Defender and its customers, he said.

Teltone has been around since 1968, when it made equipment for telephone companies’ central offices. By the early part of this decade, slumping sales in the telecommunications industry hurt Teltone, which cut staff, racked up quarterly losses and saw its stock fall below 25 cents a share.

In 2002, the company’s shareholders voted to take the company private again, which helped to cut costs. In the years since, Teltone’s strength has been in systems used to remotely monitor utility substations. One such piece of technology is installed in about 85 percent of North American electrical substations.

The newly combined companies now can offer secure communications technology for the oil, gas, water, electric, transportation and chemical industries, Nicholson said.

Debra Griffith, Teltone’s chief executive officer, said in a written statement that Teltone’s buyout after nearly 40 years of operations in the Puget Sound area “provides a graceful transition for Teltone’s extensive customer base to a company with the same high standards of excellence for customer service and product reliability as Teltone.”

“In addition, our employees will have the opportunity to work for a rapidly growing leader in the industry at the Industrial Defender Bothell location in Canyon Park.”

Reporter Eric Fetters: 425-339-3453 or fetters@heraldnet.com.