Review on Nenesupply Pump Parts Compatible With Medela Breastpump Not Original Medela Pump Parts 24Mm Breastshield Valve Membrane For Medela Pump In Style Medela Symphony Swing Replace Medela Breastshield by Tom Plowman

I originally got a hand pump, which comes with a 24mm shield. I then ordered two one-piece 24mm medela shields so I could pump both sides simultaneously. Interestingly enough, it's slightly smaller than the manual pump 24mm shield. Not sure why the same company has a discrepancy in their sizes. Anyway, the manual shield is a better fit and works well with my electric pump-in-style, but after pumping for 10min, my nipple is a bit sore and rubbing on the edges (especially on the one-piece shield). I also notice a ring of skin build-up after pumping, so I was thinking they might be too small according to the medela fit guidelines. However, it seems the 27mm is too large, because I get noticeably less when pumping (a whole 1-2oz less). Nothing wrong with the design, I apparently just need something in-between. I'm going to try lubing the smaller flanges and see if that helps with comfort, and maybe order another manual pump just for the shield.