The Model 059 accurately mimics the ultrasonic characteristics of tissues found in an average human breast. The size and shape of the phantom simulates that of an average patient in the supine position. A special holding tray facilitates proper hand position during the training procedures. Protected by a membrane, the phantoms flesh-like consistency, (Zerdine? )(1) simulates needle resistance. The phantom contains several solid masses that appear isoechoic to the simulated breast tissue under normal ultrasound, but the lesions are 3 times stiffer than the background so they can be detected on elastograms. Lesions range in size from 2 mm to 10 mm diameter and are randomly positioned throughout the background.