Parameter:
Working voltage: DC 3V-5.5V
Working current: 5.3mA
Working temperature: -40℃-85℃
Output mode: GPIO
Induction degree: Less than 15 degree
Ranging range: 2cm-600cm
Ranging accuracy: 0.1cm+1%
Dimension: 45*20*1.2 mm

4 pin interface definition:
1st pin: access power VCC(direct current 3V-5.5V )
2nd pin: access the Trig port of outside circuit, ranging will be triggered by input a 10uS above high level to this pin.
3rd pin: access the Echo port of the outside circuit, after finishing ranging, the pin will output a high level, the width of the high level equal round trip time of ultrasonic.
4th pin: access ground of outside circuit.

Measuring Period and Range Exceeding:
While the distance exceeds the measuring range of US-026, the high level signal will output through Echo pin still, and the width is 66ms.
Measuring period: After exporting a high electrical level impulse by ECHO pin, the next measurement can be taken. So the measuring period is decided by the distance, shorter distance means narrower impulse width, the measuring period will shorter too. 
The object is further than the measuring rang, the width of impulse is the longest, about 66ms, so the period should slightly larger than 66ms, such as 70ms, that is enough.
Distance=(high level lasting time *340m/s)/2. 

Packing List:

5 * US-026 ultrasonic module
2 * Acrylic mounting bracket
10 * Male to female Du-Pont wire