Willow Breast Pump Sizing Insert Set - Smaller Flange Fit | Willow – Willow Pump Skip to main content

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Willow Sizing Insert Set (2-pack)

$19.99
HSA/FSA
25% OFF
Willow Sizing Insert Set (2-pack)
Willow Sizing Insert Set (2-pack)
Willow Sizing Insert Set (2-pack)
Willow Sizing Insert Set (2-pack)
Willow Sizing Insert Set (2-pack)
Willow Sizing Insert Set (2-pack)
Willow Sizing Insert Set (2-pack)
Willow Sizing Insert Set (2-pack)
Willow Sizing Insert Set (2-pack)

Willow Sizing Insert Set (2-pack)

$19.99
Our silicone sizing inserts help to optimize output for moms who measure between 13 mm and 27 mm.

Save 25% with code PUMPING25

13mmwhat’s my size?

Find your flange fit. Pump with confidence.

When it comes to wearables, sizing is different — you'll need a fit that's more snug. Most moms find that adding 1-3mm to their nipple size (or 0-2mm if you're pumping with Willow 360) results in optimal output and comfort.

Still need your nipple measurements? Try our sizing guide

Measured Nipple Size

 Willow Recommended Size Flange / Insert
9-11mm 13mm insert in 24mm flange
12-13mm 15mm insert in 24mm flange
14-15mm 17mm insert in 24mm flange
16-17mm 19mm insert in 24mm flange
18-20mm 21mm flange
21-23mm 24mm flange
24-26mm 27mm flange

Sizing inserts can only be used with a 24mm flange or 24mm container insert.

Questions? Our experts can help.
1-888-WILLOW-3

How To Find Your Nipple Size

Step 1: Get a measuring tape

Measure the diameter of your nipple at its base while erect to determine its size accurately.

Step 2: consider sizing up

Most moms find that adding 1-3mm to their nipple size results in optimal output and comfort.

Step 3: take a look at our chart

Match your measurements to our sizing chart to find your recommended size flange / insert.

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Willow Sizing Insert Set (2-pack)

$19.99

Replacing Your Parts

For optimal output, replace every 90 days (or when you notice discomfort or signs of wear).

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