Bundle & Save
Mom-approved bundles for breast care, milk storage, and pumping on the go
Willow Sizing Insert Set (2-pack)
HSA/FSA
HSA/FSA
Willow Sizing Insert Set (2-pack)
Our silicone sizing inserts help to optimize output for moms who measure 21 mm or smaller and up to 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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