Most of what goes wrong with an order in this category traces back to one of two details. Neither is complicated, and both are on the product page already.
Toughened is stated or it is ordinary glass
We repeat the supplier wording and add nothing.
Check the parcel while the courier is there
Transit damage on glass is far easier to settle when it is found at the door.
Why we publish it this way
We publish the stated width and height of every mirror in inches as the supplier gives them, and we do not round the figures, because a 30 x 22 inch mirror over a 24 inch basin looks wrong by exactly that margin.
A blank field on one of our pages is deliberate. It means the supplier did not give that number, and inventing one would be worse than leaving it out.