There is no need to use the bust measurement; all bras fasten at the back and shoulders. It automatically adjusts to your body shape.
For maximum coverage – stick to the larger size.
For bolder coverage – stick to the smaller size.
*Example: A customer with a C cup bra size and unsure between size S and M.
If you prefer more coverage on your body, go for the larger size, size M.
If you prefer the bra to be more exposed on your body, go for the smaller size, size S.