Graduated Plug
My collection already has a number of sounds for fun and experimentation, but when I came across this interesting plug, I had to give it a whirl.
Unlike my other tapered sounds, this one is step-wise graduated in .5mm increments and is marked along the shank as the size increases. This allows you know exactly what size works for you as well as to help you push to the point of “cannot take any more”. For me, that’s well before this rod maxes out at 10mm. Indeed, about 8.5mm is the most can handle. That’s well and good given that this rod doesn’t have a flared end to prevent all 90mm of it from sliding completely in if such a large 10mm size could even fit.