They also made a smaller version of the duck call, about 6" long, for squirrels. You tapped it against your thigh or tree trunk and it made the third-best squirrel call I ever heard. There are some imitations on the market now that are not worth anything, whoever makes them apparently has never heard a squirrel bark or chatter. The best squirrel call I ever had was made by Herter's in the '60's and it sounded exactly like a squirrel, it was the type you blow into. But mine wore out in the '80s, Herter's was only a memory, and despite trying literaly a dozen or more since then, none are squirrel calls, they are most likely re-labeled duck calls because that is what they sound like. My father could place a half-dollar in the circle made by his left forefinger and thumb, then strike it with another half-dollar and the sound was even better than the Herter's call. I can't do it nearly as well, even using the old real half-dollars, not the pot-metal ones in circulation today.
My wifes dad gave her one he used to use when she started hunting ducks with me about twenty years ago. I remember them from high school. You are right they make a feeding chuckle better than most callers. The only bad thing is all the movement in the blind. She does not go on a decoy hunt with out it and she kills lots of ducks. Enjoy! Wayne