The 04420026 from PDQ is a versatile 75 KHZ ultrasonic sensor measuring 15' in length. The cord is 1.5" in diameter. It's a versatile sensor, pairing easily with most of the LaserWash systems including LaserWash M5, LaserWash G5, LaserWash 360, LaserWash Pro Touch Tandem, and LaserWash Pro Touch Icon systems.