Flange reducers are made of BPA free, made of food-grade silicone. Silicone allows for a more comfortable and effective pumping experience. 
 
Flange reduction inserts compatible with the following flange brands:
Primary Pumps 
Medela 
Spectra
Lansino  
Ameda  
Baby Buddha 
 
Pumping Cups
​​​​​​​​​​​​​​​​​​​​​Momcozy silicone cups
Legendairy Milk silicone cups
Tsrete Wearable silicone cups
Freemie cups
 
Wearable Pumps
Willow 24mm flanges
Momcozy
 
These reducers do not fit flanges smaller than 24mm and larger and 25mm.