I agree with Michael. It is a current design of a size 6. The B210 which according to WalterBiensur was probably just a reference number used in the UK. The reference number referred to a size 6 set from the late 80s to 90s. The difference between the “B210” and the modern size 6 lies in the design of the king and queen, rooks, bishop and knight. The biggest factors I would say is the queen’s small dimple on her crown, the thin cross on the king, and the top of the rook. The bishop’s head is also different and there are some differences in the knights beak and a few other things.
Here is my antiqued version which incidentally did not come with the B210 reference number on the box.
Here is @Audioq’s non-antiqued B210 set.
Here is @Ronbo710’s antiqued B210 set.
Thanks for that reply @MCH818. The bishops are actually so different! I hadn't spotted that. I'm still very happy with these and I think the large ball on the queen is growing on me. However, I'll be keeping my eyes open for some of the older sets because that King's cross and the finish look amazing!
Here's an image of a Chavet B210 posted by another forum member.
The only difference is mine isn't polished. I'm guessing it was unfinished to begin with. The seller told me he had waxed them.. some of the wax is visible in the eyes of the dark knight and on his mane. I wasn't sure if it had to be polished to be considered a B210.