Built in 1999, by Main Iron Works Incorporated of Houma, Louisiana (hull #403) as the Kimberly Colle for the Colle Towing Company of Pascagoula, Mississippi.
In 2010, the Colle Towing Company was acquired by the Signet Maritime Corporation of Houston, Texas. Where the tug was renamed as the Signet Defender.
Powered by two, EMD 16-645E6 diesel engines. With Reintjes WAF1961 reduction gears. Turning two, 108(in) by 117(in) four bladed, stainless steel propellers. She is a twin screw tug, rated 5,070 horsepower.
Her electrical service is provided by two, 75kW generator sets. Driven by two, Detroit Diesel 6-71 diesel engines. The tug's capacities are 97,277 gallons of fuel, 6,000 gallons of potable water, and 400 gallons of lube oil.
The towing equipment includes a Skagit, SMATCO, double drum, towing winch. Outfitted with 2,000(ft) of 2.25(in) towing cable on each drum. Her bow winch, is outfitted with 150(ft) of 2.25(in) Samson Quantum-8 HMPE hawser.