I found a mute in the bottom of a little Kimball spinet last week, and I've been using it ever since. I like the patina on the handle, the aged rubber has a nice feel to it as it slides between the strings, and the corners of the front edge are rounded, not square like my Schaff mutes. I looked at it more closely today and found "Tonk Bros Co. Chicago" in little raised letters on the side.
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