Is this a Purr pot you are talking about? A pot with a piece of normally grey slate with high sides, no sound board and one BIG exit hole used for soft calling. Does a Great job of soft purring and soft clucks.

If it is, there are many call makers that make them and yes they do have their place in your vest. They make some of the most realistic Soft Purrs and Clucks. They are normally used as a finishing call for those stubborn gobblers that hang up at 75 to 100 yards out of gun range and want the hen to come to him. Use it and most of the time the gobbler will come to the end of your gun barrel, as long as he doesn't see movement. Remember he KNOWS exactly where the sound is coming from and will ZERO in on that spot looking for that perceived hen.