BeauGen's breast pump cushions are like a thin layer of pillowy heaven between you and the hard plastic of your pump. Simply inserting the cushion into the flange allows for a pleasant surprise: these breast pump cushions reduce pain and discomfort for those experiencing soreness and sensitivity. Women having trouble expelling enough milk can also enjoy the benefits of these pump cushions. Thanks to its soft and stretchy material, each 1mm-thick cushion fits breast shield sizes 21mm-27mm, and should be replaced after up to 30 days depending on frequency and use of care. The breast pump cushion will reduce the diameter of the flange by 2mm, meaning you may require a larger flange to accommodate. The cushion is compatible with most breast pump brands and accessories on the market.