Can someone confirm what the “valve membrane” is for spectra? : r/HumansPumpingMilk

Name: Can someone confirm what the “valve membrane” is for spectra? : r/HumansPumpingMilk
SKU: 90726341862
Price: 21.5 USD
Availability: PreOrder
Rating: 4.7 (419 reviews)

$ 21.50 · 4.7 (419) · In stock