This is a very rare Herman "Swingmaster" wah-wah mute. The second image is believed to be an advertisement from the late 1930s. While there are some dents and distortions, and it's not in perfect condition, it is in a perfectly usable state. This is a mute you don't see very often, and I'm releasing it from my collection as part of a decluttering effort. I might regret this... I've been checking overseas markets for a long time, and I haven't found even a handful of these. If you've been looking for one, don't miss out! Thank you very much.