We recently moved to a new house, and as our downspouts were backing up I realized there was a clog somewhere in the buried drain tubing. There was no evidence anywhere of where this tubing went or terminate. I tried flushing it with a power washer hose but I never found any water puddling. So I bought this sensor snake, and reeled out the snake while monitoring where the end was, about five feet at a time, until about 35 feet later it was stuck in the tubing. As I knew where the end was, I was able to dig right there, and sure enough, there was the end of the tubing, with a trickle of water coming out. I removed a one-foot plug of leaves and mud from the tube, and mission was accomplished. I have now extended the tubing and know where everything goes; and saved a countless amount calling a contractor to do this work. I am very impressed with this unit and am loaning it to a friend who has a similar situation. It is well made, easy to use, accurate, and a good value!