Circuit with two Ultrasonic Sensors.

Other Hardware Sensors
4

You cannot ping them both simultaneously as the beams will interfere.

Also, with the following code, the pulse output from the second sonar will be coming
out while the first pulsein() is still reading, I think, so there is no pulse for the 2nd
pulsein() to read.

duration = pulseIn(inPin, HIGH);
durationk = pulseIn(inPink, HIGH);