Suzuki SHINOBIX – This harmonica silencer. I guess you can now play your harmonica like a true ninja? harmonica muting
DIY harmonica silencer , Harmonica muting, Acoustic test with scarf
https://www.reddit.com/r/harmonica/comments/9sr4bd/does_anyone_have_this_and_does_it_work
https://global.rakuten.com/en/store/centralmusic/item/10009972/