Willow Breast Pump Sizing Kit
The Willow Breast Pump Sizing Kit comes with 5 flange sizes, per Willow. Kit of five insert sets (13, 15, 17, 19 and 21 mm) that fit into 24 mm flanges, plus a nipple sizing tool, a sizing guide and a virtual visit with a Willow sizing specialist.
- $24.99List price
How the Breast Pump Sizing Kit stacks up
Against the 34 pump parts and flange inserts we track. The shaded band is where the middle half of them fall; the dot is this one.
Within the typical range for pump parts and flange inserts (3 to 5).
Within the typical range for pump parts and flange inserts ($10.99 to $52.49).
What sets the Breast Pump Sizing Kit apart
Measured against the 34 pump parts and flange inserts we compare, from each maker's published specs.
- 5th most flange sizesof the 17 pump parts and flange inserts with it published: 5
Next to its closest matches
- Willow Sizing InsertsNext to it, the Breast Pump Sizing Kit is 1 fewer size; $5 more.
- Bodily Cushy Silicone Breast Pump FlangesNext to it, the Breast Pump Sizing Kit is 3 fewer sizes.
- Ameda Universal Soft Breast Pump Flange InsertsNext to it, the Breast Pump Sizing Kit is 1 fewer size; $13 more.
Fit and use
As Willow lists it.
| Sizes | 13 mm, 15 mm, 17 mm, 19 mm, 21 mm |
|---|---|
| Material | silicone |
Fits these pumps
Willow says it fits: most 24 mm flanges (maker: compatible with almost all 24 mm flanges).
Listed features
- Five insert sizes in one kit
- Works with most 24 mm flanges from other pumps
- Labeled HSA/FSA
Where to buy the Breast Pump Sizing Kit
Prices and availability change. We may earn a commission from some links.
- Check for recalls: Search the agency's recall list with the model number and date code from the label: FDA recalls list.
- Breastfeeding and pumping: see the AAP's breastfeeding pages and the FDA's breast pump page. Check the label and the maker's instructions, and ask your pediatrician about your child.
Full specs
| Willow Breast Pump Sizing Kit | |
|---|---|
| Type | Pump part or flange insert |
| List price | $24.99 |
| Fits | most 24 mm flanges (maker: compatible with almost all 24 mm flanges) |
| Sizes | 13 mm, 15 mm, 17 mm, 19 mm, 21 mm |
| Material | silicone |
| HSA/FSA | Eligible, per the maker or supplier |
More parts
- WillowSizing Inserts$196 flange sizes$19.99
- BodilyCushy Silicone Breast Pump Flanges$278 flange sizes$27
- AmedaUniversal Soft Breast Pump Flange Inserts$116 flange sizes$11.99
- AmedaCustomFit Breast Pump Flanges$105 flange sizes$10.99
- LansinohComfortFit Breast Pump Flange Inserts$93 flange sizes$9.99
- ZomeeUniversal Inserts$95 flange sizes$9.99
- Frida MomBreast Pump Flange Insert$73 flange sizes$7.99
- Pumpin' PalOptiFit Angled Flange Set$49$49.95
Where these specs come from
Last checked 2026-11-05. Spot something wrong? Tell us. Read our editorial and safety policy and corrections.