Like I said, I don’t have a good way to measure it. I pulled out a tape measure. 11mm sounds like a good guess for the length (it’s hard to get a tape measure in there). I think the diameter is smaller, about 5mm.
I certainly appreciate your very kind offer. But I won't take you up on that this time because I have already completed my video, and right now I am merely adding content to the Text Description (which appears beneath the video on YouTube) to give specific recapping guidance to folks who have an extended keyboard (which I don't own) or a newer mouse like yours (which I also don't own). I will post a link to that video soon. Thanks again!
Below is my just released video. I will post it separately in another thread too so others can easily find it. My humble and sincere thanks to all of you in this thread. I put details of our discussion inside the text description under the video, which can only be seen when viewing the video on YouTube.