Our silicone flanges work great in pumping bras! It just takes a little tweak to allow enough room to suction them onto the breast before they're full fastened. We have info on page 10 of our silicone flange instructions — here's some of what it says:
For pumping bras that clip onto the strap, thread the first silicone flange through the hole in the bra but don't fasten it yet. Then attach the flange to the bottle and pump and suction it on. Once the flange is attached, clip the bra onto the strap. Repeat on the other side.
For pumping bras that zip up the middle in front, zip it only 2-3 inches at first so you still have room to suction each flange onto your breasts. Then zip it the rest of the way after both sides are attached.
For homemade pumping bras (that used to be sports bras) or types that don't fasten, thread the flange through the holes in the same way but leave the arm straps down until both sides are suctioned on and then pull the arm straps up over your shoulders.
We don't recommend nesting a silicone flange inside a hard-plastic flange for hands-free pumping because it's extremely difficult to get a silicone flange on deeply enough for full milk drainage since you can't turn the funnel part of the flange back over the tunnel when it's inside another flange.
If you have any difficulty getting this working, we have videos on our YouTube channel from real moms showing how to use different kinds of pumping bras with our silicone flanges. If that doesn't help, please let us know and our inhouse lactation consultant will be happy to walk you through it.
Reviewed by Diana West, IBCLC
June 10, 2021