Basically two techniques are available for examination of the hands: 1. The transducer is used in conjunction with a concave standoff pad, preferably one having a variable curvature. 2. The hands are immersed in a gas-free water bath. In this technique the very high impedance jump between the water and skin produces exceptionally high-level echoes on the skin surface. (The height of the impedance jump depends on the difference in the sound transmission velocities of the adjacent media.)