Yeah, they aren't an EXACT replacement part, as the originals are rubber and these are a sort of soft plastic. I am not the discoverer of these, just a relayer of information. I finally installed mine just now after receiving them a couple weeks ago. Not perfect, but way better than $250.00 plus for new cowls.
Previously I had used a contact cement to re-attach the old ones. They finally rotted off and I had to carefully scrape/remove the contact cement & remains. For those who are worried about the "looseness" in some installations, just use a general contact cement in the installation. (I may still add that with mine...) It will come off if you need to re-do this in another 5-6 years...