Built in 1952, by RTC Shipbuilding Incorporated of Camden, New Jersey (hull #209) as the Pottsville for the Reading Railroad Company of Philadelphia, Pennsylvania.
In 1961, the tug was acquired by the McAllister Brothers Towing Company of New York, New York. Where she was renamed as the Michael J. McAllister.
In 1970, she was acquired by the Mobile Towing and Wrecking Company of Mobile, Alabama. Where she was renamed as the William A. Weber.
In 1971, the tug was acquired by the Moran Towing Company of New York, New York. Where she retained her name.
In 1977, she was acquired by the American Pacific Industrial Leasing Corporation of Portland, Oregon. Where the tug was renamed as the American Endeavor.
In 1978, the tug was acquired by E.N. Bisso and Son Incorporated of Metairie, Louisiana. Where she was renamed as the Beverly B.
In 1997, she was acquired by Pacific Fuel Services Limited of Panama City, Panama. Where the tug was renamed as the Valviria.
In 2008, she was acquired Siministros Marinos Liited of Panama City, Panama. Where the tug retained her name.
She was powered by a single, Fairbanks-Morse 10-38D diesel engine. The tug was single screw, rated at 1,600 horsepower.