Originally Posted by
Metaluna
I just bought a card of 6 KMC links (before I read your post, now I wish I looked harder for the reusable version
). Here is a picture of the top of the package. Notice that they call out the details (the "Safety Lock" features highlighted in red on the drawing) that make the link non-reusable. I don't know what the reusable version looks like, but I do intend to try to reuse these (at least the non-reusable one that came with my KMC chain).
Who knows really what the difference is between the CL555R and non-R version. Even KMC's own website uses the same URL for the photo on both products. I would note that there is no such thing as a reuseable 11S Missing Link (per KMC) that is made for campagnolo chains for some reason.
M/L-11R - KMC Chain