Nipple Sizing with Lacteck Baby Motion Flanges 

Dec 3, 2020 | Lacteck | 4 comments

Updated 2022

Lacteck Baby Motion flanges are a great alternative to the standard hard plastic flanges that come with our pumps. They are a soft silicone-based material that compresses the nipple while pumping. Obviously, this is so much more wonderful than hard plastic. However, when it comes to sizing you should know that they are not true to size.

Lacteck come in sizes 27mm, 24mm, 21mm, 18mm, 15mm and just released 13mm. From helping thousands of moms we have all discovered that all their flanges are roughly 2mm larger than advertised.

  • 27s they fit like a 28/29mm,
  • 24mm fit like a 25/26mm,
  • 21mm fits like a 22/23mm,
  • 18mm fit like 19/20mm, and
  • 15mm fit like 16/17mm.

13mm was recently released and reports are the fit is exact. However, as this is still new product, please feel free to give me your feedback.

Be aware that if you do get Lactack Baby Motion Flanges you will need base connectors for pumps like Spectra, BabyBuddha, BellaBaby, ect… They require two piece connectors like the ones found for Medela and Lansinoh pumps. You can find them here. 

So when you are choosing which size to get, this little tip of knowledge will come in handy. Still don’t know what your flange size is? Get the Nipple Queen Ruler where we can take the guesswork out for you and get  the exact flange size you need regardless of the pump or products you chose. The number on the ruler is the size to buy! use code SAVETHEMILK for 10% off 

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  1. Amanda

    I found this article after ordering these flanges. They are really comfortable but after reading this wondering if I should have sized down? I was recommended a flange size 21mm which of these should I g by be using the 18mm or 21mm. I pump exclusively with the Elvie.

    • Crystal Nelson

      If you find that the size you are using is comfortable and allows you to empty, then there is no reason to change sizes.

  2. Raychel

    Is the generation 3 still large? I was recommended size 18 but wonder if I need to side down. I see your post is from 2020 so didn’t know if they have updated their flange sizing

    • Crystal Nelson

      They are still a little big. I have been seeing moms post that the new sizes start out the right size but tend to get a bit large when washing. I still think they are a great option!


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