Used one in the mid 70’s on a commercial basement fire, and again in a residential basement fire. The one we used was attached to a 3’ long, 2 1/2 pipe attached to the nozzle, and two 3’ “arms / brackets” that hinged out 90 degrees so that you could drop the pipe down the hole and the “arms” rested on the floor, thereby suspending the pipe and head at about 30” into the hole. The only drawback was that if you didn’t limit flow, the basement would fill up and flood in no time! Other than that, it was a great tool.
I feel like these might see some use in the future with EVs. Knock the fire most of the way down, put this on something that can hold it up, maybe some type of monitor, stick it through a window and let it sit there keeping water on that fire instead of having a guy sit there with a fog tip, hosing down a car that's not going out until the batteries are completely burnt.