An enhanced version of the z.one convertible ultrasound system, z.one ultra, appeared this week from Zonare Medical Systems. The upgrade, first shown in March as a commercial product, automatically adjusts gain and brightness and traces spectral Doppler waveform. A key feature is its ability to optimize an image with a single button push to account for varying speeds of the ultrasound beam as determined by the body's build — thin, obese, or in between.