Ultrasonic Flaw Detector Defectoscope 9999mm Range 220V Range: (0 ~ 9999) mm at steel velocity Bandwidth: (0.5 ~ 15) MHz (amplifier bandpass) / Display delay : 20 to 3400 s Material Velocity: (1000 ~ 9999) m/s Probe delay /zero offset : 0 to 99.99 s / Accuracy 1 dB / High speed USB : 2.0 port Power supply: DC 9V; lithium ion batteries work for 8 hours or more