TromboneChat

I’m looking at a nice King 2B that belonged to a friend who passed away. King 28 - specs? It feels pretty 12C-ish to me but a nice rounded Tim.

King 28: Cup I.D.: 24.50mm / 0.965" | Throat: 5.94mm / 0.234" (Supplied with my friend's 1967 King 3BSS)
King M21: Cup I.D.: ~ 24.40mm / 0.961" | Throat: 5.85mm / 0.230" (Supplied with my 1958 King 2B)
Bach 12C: Cup I.D.: 24.50mm / 0.965" | Throat: 5.85mm / 0.230"

Per King, the King 28 & M21 mouthpieces are the same size. Mine measure very slightly different. Both rims are "rounded."

Thanks.

I think the King mouthpieces may be a bit more conical than the Bach 12C, but I can't confirm.