I have a friend asking to identify a particular power cable, and I wanted to check whether these sorts of "Identify this" questions are on-topic for Home Improvement before asking. I know other sites have made an effort to do-away with the general "Identify This" trend.
We've those questions from time to time in the past, and the community appears to allow them. When possible, give context on what you're trying to do by identifying the object. If something is broken, there may be other ways to fix it. And if you need a part to fit in X, then let us know what X since there may be something designed specifically for them.
What we do discourage is "where can I buy this?" Realize that identify this questions are often a small step away from shopping advice. When the OP would be happy to get a link as an answer, we tend to close the question, because they attract poor link-only answers and spammers.