The silicone cups become very flimsy after a couple sterilizations, its easily clogged due to thin silicone flaps that either close or dont with the smallest amount of residue, and its not a very "good" suction. Instead of pulling / massaging more of the nipple / areola, it tugs on a small section of nipple making it painful after a few minutes, and slight blood blisters are not uncommon. All in all, if it wasnt for being given this pump, i would be bitter about being out money on this product. Looking into purchasing something different.