Choosing a Willow breast pump flange size
How to choose the right flange size for a Willow breast pump.
Willow Pump Willow Sizing Insert Set: They are designed for the perfect fit and performance with Willow and make pumping more comfortable for mamas with smaller flange sizes. Sizes offered are 13mm, 15mm, 17mm, 19mm, 21mm and 27mm. Willow Pump Willow Sync Flange Set 24mm (2-pack): The flanges are 24mm. Designed for Willow Sync pumps. Willow Pump Wave 2-in-1 Double Manual Wearable Breast Pump + Cups: It includes a soft 24 mm silicone flange. The checked facts do not explain how to measure for a flange size.
| Product | Why | Flange size | Pack size | Compatibility |
|---|---|---|---|---|
| 1. Willow Pump Willow Sizing Insert Set sold by onewillow.com | They are designed for the perfect fit and performance with Willow and make pumping more comfortable for mamas with smaller flange sizes. | Sizes offered are 13mm, 15mm, 17mm, 19mm, 21mm and 27mm. listing | The sizing inserts come as a 2-pack. listing | - |
| 2. Willow Pump Willow Sync Flange Set 24mm (2-pack) sold by onewillow.com | The flanges are 24mm. | The flanges are 24mm. listing | Sold as a 2-pack. listing | Designed for Willow Sync pumps. listing |
| 3. Willow Pump Wave 2-in-1 Double Manual Wearable Breast Pump + Cups sold by onewillow.com | It includes a soft 24 mm silicone flange. | It includes a soft 24 mm silicone flange. listing | - | It connects to traditional breast pumps for flexible pumping options. listing |
Also cited in the text
- Willow Pump Willow Sizing Insert Set, Purpose: They are designed for the perfect fit and performance with Willow and make pumping more comfortable for mamas with smaller flange sizes. listing
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Written 2026-10-16T21:57:56.466Z.
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