... . Technical Parameters:Structure: portable and trolley, KJ-4001, 4002, 4003 and 4003(workstation)Display mode: Convex array: B, B/B,4B, B ... interpolation, etc.Frequency conversion: 2.5MHz/3.0MHz/3.5MHz/4.0MHzCalculation: distance, perimeter, area, heart rate, pregnancy week (BPD, GS ... applied to check intrauterine equipment, pregnancy and so on.. KJ-4003 Trolley B Ultrasound scanner