【No Need to Choose Flange Inserts】 KISSBOBO Electrical breast pump is equipped with 135-degree angle large petal design and 24-flange caliber breast collector, adapting to mothers with 14MM to 23MM diameter nipples, helping 90% of mothers to easily purchase breastpumps, and at the same time, reducing the time spent on choosing flanges. If your nipple size is less than 14MM or more than 24MM, please contact KISSBOBO customer service team immediately, we will help you get the right flange.