10 pcs 365buying HC-SR04 Arduino Ultrasonic Distance Measuring Sensor Module/ Ultrasonic Distance Rangefinder
The main technical parameters:        1: Voltage: DC5V 2: Static current: less than 2mA        3: level output: high-5V 4: level output: the end of 0V        5: Sensor angle: not more than 15 degrees 6: Detection distance: 2cm-450cm     7: High precision: up to 0.3cm Board wiring, VCC, trig (control side), echo (receiving end), out (empty feet), GND