Lot of 14 Heavy Duty 2.5in Steel Hex Pipe Plugs Threaded Industrial Fittings Used - Good, surface rust and oxidation present, general wear and grime from previous use. 14 heavy-duty hex pipe plugs, each approximately 2.5 inches in diameter and 1 inch tall, threaded design for industrial or plumbing applications. Cast iron material. Model -05 2. MPN: Does Not Apply. End A Diameter: 2 1/2 in. Brand: of. California Prop 65 warning.