Brush diameter is actually 2 1/4" of natural boar bristles. Bristles are rather stiff as new but should soften slightly with use. Ceramic core looks solid. Outer finish of the wooden handle is just acceptable with the hanger hole lacking any sealer (had to seal it to keep water from entering the wood during cleaning).
This type of natural bristle brush was surprisingly hard to find locally.
All in all a great value!