"Support thickened 4MM high-strength Acrylic board/Unique design featuring simple and sturdy structure, which can withstand greater impact.Scope of application:obstacle avoidance by/ distance-measuring of objects/ liquid-level detection/ public security/ parking lot inspectionSpecification:1. Operating voltage: DC5V2. Quiescent current: ?2mA3. Voltage output: high:5V4. Voltage output: low: 0V5. Detection angle: ?15°6. Detection distance: 2cm-450cm7. Accuracy: 3mmConnection mode: VCC, trig(Control end), echo(receive end), GNDBasic working principle:i) Adopts IO interface TRIG ranging, give at least 10us high level signalii) The module will automatically transmit eight 40KHZ square waves and detect whether there are returning signals.iii) If any signal returns, a high level will be output through ECHO, and the duration of the high level is the time needed for transit to receipt by ultrasonic. Then the measuring distance=duration of high level* 340m/s*2;"