Review on Maymom 15Mm Flange Insert Compatible With Elvie Single/Double Electric, Elvie Stride Cup (24Mm), Compatible With Medela PersonalFit Flex Shield, Not Original Elvie Replacement Pump Parts by Tom Schuster

I got these for more comfortable pumping. The plastic 21mm flanges offered by Motif Luna can get uncomfortable after a while for me. These silicone inserts help. They are firmer than I expected but still soft enough to be comfortable. I tried them with the 24mm flanges that come with my pump but found it was impossible to fit them inside the flange. Luckily I had the 28mm flanges still, and these inserts fit perfectly in those. So beware if you're going just off of the product description!