I must say your service was truly inspiring. While it was a simple part I received great advice on how to change the internal grind setting on my Baratza Virtuoso. I was directed to the service tutorials on Baratza's website and now it actually grinds fine enough for may Rancillo Sylvia. It has never done that and I was going to replace the grinder. You guys saved me hundred of dollars. Thanks so much.
I go through one or two a year. Baratza should include a bunch of these in the box with each grinder.
I have gone through about one of these a year with my Preciso. They crack, and when that happens you can't get the grind fine enough. My understanding is they crack easily in order to protect the more sensitive and expensive bits of the grinder. So I guess that's a good thing, though it also means they will break even if you're fairly gentle with your gear. They are inexpensive and so my advice is to buy a few at a time, so you are never left needing a new one.