3.9
Rated 3.9 out of 5 stars
251 Reviews

Willow® Sizing Insert Set
(2-pack)

$19.99

Our breast pump sizing inserts are designed to help optimize comfort and output for moms who measure smaller than 21mm.


Available in sizes 13mm, 15mm, 17mm, 19mm and 21mm for use with 24mm Willow flanges and containers.


Did you know: you should replace pump parts every three months for optimal performance. Normal wear and tear can impact suction and output! Having extras on hand is helpful in the event that you lose a part, too.


Select a size
What's my size?
  • 13mm
  • 15mm
  • 17mm
  • 19mm
  • 21mm
Free shipping on orders over $69

2 ways to pays with

Insurance & HSA/FSA

  • FSA/HSA reimbursements eligible

3.9
Rated 3.9 out of 5 stars
Based on 251 reviews
Total 5 star reviews: 154 Total 4 star reviews: 22 Total 3 star reviews: 22 Total 2 star reviews: 13 Total 1 star reviews: 40
71%would recommend this product
251 reviews
  • Sarah S.
    Verified Buyer
    I recommend this product
    Rated 5 out of 5 stars
    Comfy and cute!

    These are comfy and cute. They pair with other pumps/flanges as well. They are thinner than other sizing inserts I’ve purchased, so I am more careful when removing them.

  • Rebecca
    I recommend this product
    Rated 5 out of 5 stars
    5 Stars

    Love these! Use them with all of my pumps!

  • Jessica
    I recommend this product
    Rated 5 out of 5 stars
    5 Stars

    Love! This has made my work flow soo much easier. And once you get the hang of it (using a time or 2) I don’t spill any milk and it pumps just as much as my wall pump, and I’m a low supplier! 10/10 recommend

  • Stacy W.
    Verified Buyer
    I recommend this product
    Rated 5 out of 5 stars
    Fits like a glove

    I really like how the inserts fit easily inside the flange, and don’t fall out! Makes traveling with the pump easy and using it even easier. One less piece to have to remember.

  • Dakota G.
    Verified Buyer
    I recommend this product
    Rated 5 out of 5 stars
    Sizing inserts

    They're a must have. Without them, we were getting novelty pencil eraser nipples using the flanges alone. I'm talking entire tater-tot titties.

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