The rubber ring on my 24-70 f.28 lens started to wear out. It expanded, lost its grip on the lens barrel and came loose. I contacted Nikon support and they told me that this is normal wear. It is actually not a surprise, my 24-70 is the workhorse of my lens...
I know that unboxing videos are very nerdy. But it is kind of fun making them, so here is another one. If the weather clears up tomorrow, I will go out and give it a test...