A common design that follows many prototypes, these steam-powered vessels were sometimes known as "spud barges" because of the two stabilizing "spuds" that held them in position while working. Used as lighters when cargo had to be lifted on or off larger vessels, they also handled marine construction projects such as dock building, salvage and moving large rocks for break walls and riprap. The model features a detailed deckhouse, pilot house and stack, a timber stiff leg type derrick, a nonworking two drum winch, used on the prototype to power the derrick, and single drum nonworking winches used on the prototype to raise and lower the spuds. Designed for easy construction with resin and metal castings made especially for this model.