[Dixielandjazz] One of my favorite T-Bone players

[Bob Smith]

I've just been watching the excellent Tyree Glenn videos on the URL provided 
by "dixiejazzdata".

I've only heard Tyree on recordings previously, and have always assumed he 
used a Harmon mute. However, I can see that, in addition to the 
drain-unblocking wa-wa mute, he has a small mute inside the trombone bell. 
Does anyone know what type of mute this is, and what it is called?

Thanks in advance.

Bob Smith