The Single Breast Shield can be used as a replacement part or for mothers needing an extra breast shield handy at home or in the office. Purchase a different size if the current breast flange size that you are using is not maximizing milk production.
The size of the Breast Shield really matters. Pumping should be comfortable and should not hurt. For efficient milk removal and best performance of your pump, you need to have the correct breast flange size. Not having the right size and poor fit also leads to nipple damage.