What flange size are these inserts compatible with?

Willow Inserts are compatible with most 24mm flanges.

How do I clean my inserts?

The Inserts are dishwasher safe for easy clean up.

What material are the inserts made of?

They’re made from flexible silicone material that provides a snug, secure fit.

Breast Pump Sizing Kit

Name: Breast Pump Sizing Kit
Brand: Willow Pump
SKU: USK110
Price: 24.99 USD
Availability: InStock

Breast Pump Sizing Kit

$24.99

Unit price: per

Breast Pump Sizing Kit

$24.99

Unit price: per

Find your perfect breast pump flange fit with a wide range of inserts designed for maximum pumping comfort and milk output.

Free shipping with code FREESHIP

Key features

What to know

What's included

Free shipping on orders $50+

Top-ranked 24/7 customer care

Breast Pump Sizing Kit

$24.99

Better pump fit, better milk flow.

5 Insert Sets for
Inclusive Sizing

Sizing Tool to
easily find your size

Pump Sizing 101 guide

Support via Sizing  Specialist

Your milk output  will thank you.

When it comes to breast pumps, fit really matters — and fit starts with your flange. Perfecting your flange fit has a direct impact on your comfort and output while pumping.

How It Works

Measure your nipples either an hour before or an hour after nursing or pumping.
If your flange still doesn’t feel comfortable, experiment with the other inserts. (Also, make sure you’re wearing a snug but stretchy pumping bra!)
Book your session with a Willow Sizing Specialist if you need additional support

Bundle & Save

Mom-approved bundles for breast care, milk storage, and pumping on the go

20% off

New

Pump & Clean Anywhere Bundle

Pumping shouldn’t press pause on adventure. Wherever your travels take you, this pack of essentials ensure a clean and convenient pumping experience. Includes Willow Wave Manual Pump and Travel Cleaning Pack.

~~$64.98~~ $51.98