An adjustable grunt tube, you can mimic the "can" with a grunt tube but you cannot grunt with a "can".

I like the easy adjustability of the Deer Flute from River Valley Game Calls but I also have the Woods Wise 8 in 1, Primos Rubber Necker and True Talker in that order plus a couple others. The Deer Flute by far the easiest to use. http://www.rivervalleygamecalls.com It has a easy adjustable brass slide that offers which adjustments with one finger. Ask Greg / MO, Hazcon7, tkycaller, buckeyebuckhntr and many others about it.