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)

$9.99 $7.49
25% off
HSA/FSA
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)

$9.99 $7.49
Our silicone sizing inserts help to optimize output for moms who measure between 13 mm and 27 mm.
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)

$9.99$7.49

Replacing Your Parts

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

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