1. Small Size And Easy To Use; The Dual-Probe Ranging Module Can Provide Non-Contact Distance Sensing Function Of 2cm-500cm, And The Ranging Accuracy Can Be As High As 3mm; The Module Includes An Ultrasonic Sensor And Control Circuit That Integrates Transceiver And Transmitter. Mode 1 Usage Is Compatible With The Hc-Sro4 Module. 2. Ultra-Small Blind Zone Measurement. Designed With Industrial-Grade Dual Waterproof Ultrasonic Probes, Waterproof And Stable Performance 3. High Measurement Accuracy; Ultra-Close Range, Blind Zone Is Only 2cm. Stable Ranging 4. Strong Anti-Interference 5. Integrated Closed Waterproof Probe With Wire, Suitable For Wet And Harsh Measurement Situations Pulse width output: 1. Working voltage: DC:3.0-5.5V 2. Working current: Less than 8mA 3. Probe frequency: 40kHz 4. Maximum shooting range: 500cm 5. Nearest shooting range: 2cm 6. Long range accuracy: ±1cm 7. Resolution: 3mm 8. Measuring angle: 60° 9. Working temperature: -20℃-+70℃ Input trigger signal: 1. TTL pulse above 20uS 2. Serial port sends command 0X55 Output echo signal: output pulse width level signal, or TN Wiring: 1. 3-5.5V (positive pole of power supply) 2. Trig (control terminal)RX 3. Echo (output) TX 4. GND (negative pole of power supply) Note:Different Batches May Have Differences In Product Appearance, Color, And Printed Characters, Which Will Not Affect The Use Colour:As Shown Material:PCB Package Contents: 1 * Ultrasonic Ranging Module 1 String * Connecting Cable Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.