For measuring distances and sound travel times with CASSY (
524 006, 
524 018, 
524 005W2, 
524 013). A distance is determined from the time-of-flight of an impulse of ultrasound. Derivations enable velocity and acceleration measurements.
This sensor is not supported by CASSY Lab 1 anymore. CASSY Lab 2 is available as an upgrade (
524 220UP).