Breast Pump Sizing Kit
$
23.99
Free shipping & returns for Babylist orders $45+
FSA & HSA Eligible
1
Overview
Description
Find your perfect breast pump flange fit with a wide range of inserts designed for maximum pumping comfort and milk output.
The kit includes 13mm, 15mm, 17mm, 19mm, 21mm insert sets, a nipple sizing tool, pump sizing 101 guide and 1:1 virtual visit with a Willow Sizing Specialist.
Proper fit leads to comfort, and comfort leads to more milk output and fit starts with your flange.
What we about it
Helps you find the just-right breast pump flange fit.
Details
- Includes:
- 13mm, 15mm, 17mm, 19mm, 21mm insert sets
- Nipple Sizing Tool
- Pump Sizing 101 Guide
- 1:1 virtual visit with a Willow Sizing Specialist
- Connect with a Sizing Specialist for personalized guidance
- Use with any pump; they’re compatible with almost all 24mm flanges
- Fit most nipple sizes
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Customer reviews
32 Ratings
1-10 of 32 Reviews
Helped me find my right
This review was collected as part of a promotion
Helped me find my right size which has made my output so much better!
May 5, 2026
Cute and useful!
I had no idea what the proper size flange is key for maximum output. My Spectra only had size 21 and 24 while the Willow kit put me on a size 17. After speaking with my lactation consultant, I learned the sizing kit was perfect for small girls like me!
Apr 29, 2026
These work wonderful, don’t slip
This review was collected as part of a promotion
These work wonderful, don’t slip and easy to clean.
Apr 26, 2026
Takes the guesswork out of
This review was collected as part of a promotion
Takes the guesswork out of what size I needed. Comes with a size guide!
Mar 28, 2026
Helpful convenient sizing kit
Very convenient to have one product that makes it easy to determine what size you are without having to buy and return multiple products until you find the correct fit.
Mar 14, 2026
Sizing Kit Review
The sizing inserts are perfect for getting the right flange size! They are super comfortable. The best part is having a variety of sizes to try. This helped find the perfect fit. I highly recommend this product!
Mar 3, 2026
Breast pump sizing kit
This is my third baby and I was making it priority the third time around to have the correct size met for me. This kit made it incredibly easy, wish I would’ve done it sooner. Great product!
Mar 2, 2026
Such a handy kit!
This kit is so handy for a newly breastfeeding mom! My flange size changed throughout my first time breastfeeding so I anticipate that happening again with my second. It’ll be handy as I continue to breastfeed and need to adjust sizes. I also like having all the sizes in the kit so I can try out which one works best. I highly recommend this flange kit!
Mar 1, 2026
Breast Pump Sizing Kit
This kit was so nice to have at the hospital when baby was born this week! The hospital didn't have my correct size available but luckily I brought this kit with me. The willow inserts are very comfortable as well!
Feb 27, 2026
Made sizing easy
This sailing kit came with all the bells and whistles compared to others! Not only did I get the traditional paper sizing cut out but also flanges to trial. The kit included a 1:1 consult with a specialist which I thought was amazing! I now have my correct flange sizes and am excited to pump with them 🙂
Feb 26, 2026
