An ultrasonic device evaluates the sound velocity of a nail to determine the overall health of a patient and to monitor cosmetological effects of certain products on the nail. The ultrasonic device includes a handhold probe having an piezoelectric transducer encased in cover that emits high-frequency ultrasonic impulses directed towards the nail. The nail reflects returning ultrasonic echoes back to the piezoelectric transducer. The returning ultrasonic echoes vibrate the piezoelectric transducer. A processor of a computer converts the vibrations into electrical pulses. The processor evaluates amplitude values of the electrical pulses to determine the parameters of the human nail, including the thickness, density and elasticity. The parameters are displayed on a display and analyzed by a technician to determine the nail condition. The health of the person or the effect of products on the nail can be determined based on the nail parameters.
