I have ordered 5 inch diameter and received 4.3". It even says on the scale of the jaw max 4"... which is not even achievable since the nut hangs on the very last threads and I would be worried that it can damage them. I was considering Vevor a fairly reputable seller not expecting false advertisement. Other than that it is heavy duty and well machined and came super fast. It should be fine for all my needs. Hope there will not be a time when I need to deal with more than 4" diameter.