Product review (3 stars): I returned it. My plumber said it wasn't complete ...
I returned it.  My plumber said it wasn't complete and needed another part, which was  $65.  He said he'd handle getting me the right parts.  $98 for this plus $65 for the thing that actually attaches the disposer or $199 for him to bring me a disposer and all necessary parts to install it, I let my plumber handle it.