Two ultrasonic inspections of the Experimental Breeder Reactor II steam generator duplex tubing have been completed. Inspections performed on one evaporator in 1976 provided baseline data, and a subsequent inspection in 1978 revealed no change in tube condition. With the completion of the 1978 inspection, all available tubes in one evaporator have been inspected. The steam generator contains duplex tubes fabricated from Cr—1 Mo ferritic steel. Access to the bore (water) side of the tubes was gained through the steam outlet piping. The inspection included a complete volumetric (100% of the tube material) examination, measurement of wall thickness, and evaluation of the condition of the braze bonding the two walls of the tube together. The test equipment was routinely calibrated against a standard containing artificial flaws. Artificial flaws as small as 1.6 mm long X 0.25 mm deep were readily detected. The outside surface of six tubes had longitudinal indications with a maximum depth of 0.25 mm and various lengths, and the bore side of 20 tubes had longitudinal indications. The indications were approximately 0.13 mm deep X 3 m long. Both the outside-surface and bore-side indications had all the characteristics of scratches or fabrication drawmarks and had probably been present since fabrication. No circumferential indications were found.