Sizes vary between Brands and between different item, take the time to know the right size for you based on the manufacturer's size chart. If you need any more help or guidance, please contact our Customer Services team on 866-316-0162.
For example as shown in Size Chart, a 34B corresponds to a size 4 breast form
Amoena Partial Breast Form Size Chart 
Amoena Partial Breast Form Size Chart