Built in 1999, by Thoma-Sea Boatbuilders of Houma, Louisiana (hull #110) as the Dumar II for Dolphin Tugs of Golden Meadow, Louisiana. However, the tug was later renamed as the Dolphin II. She was eventually acquired by Harvey Gulf International of New Orleans, Louisiana. Where she was renamed as the Harvey Spartan. The tug was then acquired by Crosby Marine Transportation of Golden Meadow, Louisiana. Where she was renamed as the Crosby Liberty. Powered by two 12-645-E7C Turbo Kell and grid cooling diesel engines with, two Reintjes WAF2345 reduction gears at a ratio of 4.041:1, turning two 106(in) by 99(in) propellers mounted in kort nozzles; for a rated 10,500 horsepower. Her electrical service is provided by two 99kW generators driven by two GM 8v71 diesel engines. The tug’s capacities are 80,000 gallons of fuel oil, 1,100 gallons of lube oil, and 8,000 gallons of potable water. The tug’s towing gear consists of a McElroy DT-84 double drum towing winch outfitted with 3,000(ft) of 2(in) towing wire, with a McElroy hydraulic towing pin system, and a 750(lb) Danforth anchor.