Pocket, hand-hold, use conveniently;
 Cassette holder for sensor, safety in carry, frame in bend, easily for operation, also comfortable for pregnant woman
Value or curve in LCD display;
With data and time or timer function;

With inner loudhailer;
Better power management function;
Can monitor pregnant woman's SPO2 and pulse(in option);
DSP technology,  work frequency in 1MHz,ultrasound dosage is far less than
safe standard of monitoring fetal,is more safety; single lithium battery, with  battery state indication