Definitely heavy steel construction. Does the job, but not worth the price tag anymore. Ended up buying a second one from a competitor that was much lower in price and still worked.
Bought one for my wife, and she rarely uses it. She prefers to train on the same type of bar she is competing with. It does provide a smaller diameter option than the men's bar. It doesn't do anything extra special.
Best DL bar I've ever used, unfortunately it is the only DL bar I've ever used. I have been pulling with bumper plates so that makes it bend a little bit more. Not terrible but not the best from what I hear.
It has barely any knurling. But it is fat grip to work on your grip strength. I have switched to this attachment for lat pull down over traditional ones.