These membranes are uneven. One works well and the other one over stretches and does not have good suction causing the suction to be very weak. After a few minutes of tuning off the pump and turning it back on it fixes itself. I honestly rather pay more for quality ones that I’m not having to worry that they will work.

These work well. I pump exclusively so I consider myself an expert! These are worth the price and work well as a replacement. I would suggest buying them for your pumping needs.

Great substitute for spectra brand parts. These were a perfect fit and I don’t see any difference between these and the original spectra brand parts. I have used these with both a spectra S2 and a 9 Plus

Works great with my Spectra S2. Love that these come in different colors so I know which membranes are old and need to be tossed out. I just alternate what colors I order!

These work great for me! I pump 4x per day. I rotate my primary parts (used 3x per day) to be secondary (used 1x per day) every month. The colored parts have helped us immensely to keep all this straight!