Product review (5 stars): Works like a charm!
The thing I dislike most about shopping on Amazon is the lack of useful product information on replacement type parts.  From the reviews a number of people order this and it doesn't fit their sink.  Since the sellers can't seem to clearly state the size of this thing...IT IS 3 INCHES IN DIAMETER. The hole in your sink is slightly tapered so the opening will measure a little over 3". Just push it in and it will snap in place. I chose to cut out the old baffle "ears" first. If you do, be prepared to be grossed out by the muck and slime on the underside of them. This points up how nice it is to be able to pop this piece out and clean it. This is a super nice little part.  Don't know why ISE didn't design their disposers with this type baffle to begin with.