---
title: "flange insert — Niche Verdict: Skip it (33/100) | Amazon United States - Flapen"
canonical_url: "https://flapen.com/amazon/research/us/baby-products/flange-insert"
last_updated: "2026-07-14T00:33:19.636Z"
locale: en
meta:
  description: "brand-locked demand (top 5 brands take 100% of clicks) — flange insert doesn't clear our bar today."
  "og:description": "brand-locked demand (top 5 brands take 100% of clicks) — flange insert doesn't clear our bar today."
  "og:title": "flange insert — Niche Verdict: Skip it (33/100) | Amazon United States - Flapen"
---

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# **flange insert**

**Skip it**

Brand-locked demand (top 5 brands take 100% of clicks) — this niche doesn't clear our bar today.

Market size 64Growth 20Conversion 80Competition 6Returns 49Price range 0Avg price 27Brand share 0Review moat 48Quality gap 32

**Conversion**

**Great****8.3%**

search→purchase rate — share of searches ending in a sale

**Market size**

**Good****$607K**

$607K/yr · 795K searches

**Returns**

**Okay****3.1%**

return rate — above 6% kills the launch gate

**Review moat**

**Okay****1,674.43**

avg incumbent reviews — the moat a new listing must climb

**Quality gap**

**Okay****4.6★**

avg incumbent rating — lower means beatable quality

**Avg price**

**Okay****$9.25**

avg listing price — sweet spot $15–$100

**Growth**

**Bad****-9.1%**

90-day search growth — must beat 0% to launch

**Competition**

**Bad****93%**

top-5 click share — a locked-up shelf

**Brand share**

**Bad****100%**

top-5 brand share — brand-locked demand

**Price range**

**Bad****$7.34–$10.05**

cheapest to priciest tracked listing — scored on the share inside $15–$100

## **Competition**

The top 5 products capture 93% of clicks — a locked-up shelf that new listings rarely crack.

**Brands**

**4 **▼falling

**Sellers**

**6**

**Top-5 brand share**

**100%**

**Open market**

**0%**

- Nuliie44% - Nursi Luna42% - LOTBILL7% - GOCROWEEN6% - Open — no brand owns it (0%)

## **Product shelf**

Each bubble is one product — market share against review moat; bubble size tracks estimated sales, color grades how beatable the incumbent looks.

0%15%$91K30%$182K45%$273K60%$364K1001K10K Reviews — right = deep review moatMarket share (90d) ≈ est. sales

Beatable (≤4.3★) Contested Strong incumbent (>4.7★)

All 7 tracked products in this niche — three views at once, no toggling.

### **Top sellers**

by 90-day click share

[1![Nuliie 3-in-1 Flange Sizing Kit 13/15/17/19/21mm for 24mm Electric Double Breast Pump Flange/Shield 10PCS Silicone Flange Inserts to Boost Pumping Efficiency & Comfort BPA-Free Essential for Moms](https://m.media-amazon.com/images/I/41Feyi97wML.jpg)**Nuliie 3-in-1 Flange Sizing Kit 13/15/17/19/21mm for 24mm Electric Double Breast Pump Flange/Shield 10PCS Silicone Flange Inserts to Boost Pumping Efficiency & Comfort BPA-Free Essential for Moms**Nuliie**$9.68**4.6★4,179 rev](https://www.amazon.com/dp/B0CMPBBHMZ) [2![Nursi Luna Flange Inserts 10PCS 13/15/17/19/21mm for 24mm Flanges/Shield of Most Pumps Flange Sizing Kit Silicone Flanges Insert Breastfeeding Essentials Kit for New Moms](https://m.media-amazon.com/images/I/415xYbVux6L.jpg)**Nursi Luna Flange Inserts 10PCS 13/15/17/19/21mm for 24mm Flanges/Shield of Most Pumps Flange Sizing Kit Silicone Flanges Insert Breastfeeding Essentials Kit for New Moms**Nursi Luna**$10.05**4.6★2,006 rev](https://www.amazon.com/dp/B0CKZH37FX) [3![Nursi Luna Flange Sizing Kit 3-in-1 with 13/15/17/19/21mm for 24mm Electric Breast Pump Flanges/Shields 10PCS Soft Silicone Flange Inserts for More Comfortable Pumping BPA-Free Essential for Moms](https://m.media-amazon.com/images/I/41TicDjnz7L.jpg)**Nursi Luna Flange Sizing Kit 3-in-1 with 13/15/17/19/21mm for 24mm Electric Breast Pump Flanges/Shields 10PCS Soft Silicone Flange Inserts for More Comfortable Pumping BPA-Free Essential for Moms**Nursi Luna**$9.87**4.6★2,081 rev](https://www.amazon.com/dp/B0CY81WHD5) [4![Flange Insert 13/15/17/19/21mm 10PCS Compatible with Momcozy S12 Pro/S9 Pro/S12/S9/Medela/Spectra etc Electric Breast Pump 24mm Flange/Shield Reduce 24mm Tunnel Down to Correct Size](https://m.media-amazon.com/images/I/41OcGg5lVUL.jpg)**Flange Insert 13/15/17/19/21mm 10PCS Compatible with Momcozy S12 Pro/S9 Pro/S12/S9/Medela/Spectra etc Electric Breast Pump 24mm Flange/Shield Reduce 24mm Tunnel Down to Correct Size**LOTBILL**$7.34**4.6★583 rev](https://www.amazon.com/dp/B0CL96VP1C) [5![Flange Inserts 13/15/17/19/21mm 5pcs Suitable for Medela Spectra 24mm Shields/Flanges Compatible with Momcozy S12 Pro/S9 Pro/S9/S12 Wearable Breast Pump Reduce 24mm Tunnel Down to Correct Size](https://m.media-amazon.com/images/I/31RZ9-jx9hL.jpg)**Flange Inserts 13/15/17/19/21mm 5pcs Suitable for Medela Spectra 24mm Shields/Flanges Compatible with Momcozy S12 Pro/S9 Pro/S9/S12 Wearable Breast Pump Reduce 24mm Tunnel Down to Correct Size**GOCROWEEN**$8.01**4.4★2,046 rev](https://www.amazon.com/dp/B0BKH4TX4J)

**~~View all top sellers →~~**

### **Newest**

by launch date

[![Nuliie 5-in-1 Flange Sizing Kit 12/14/16/18/20mm for 24mm Flange/Shield of Most Pumps 10PCS Silicone Flange Inserts to Boost Pumping Efficiency & Comfort BPA-Free Pump Essential for Moms](https://m.media-amazon.com/images/I/51GT53yIMsL.jpg)**Nuliie 5-in-1 Flange Sizing Kit 12/14/16/18/20mm for 24mm Flange/Shield of Most Pumps 10PCS Silicone Flange Inserts to Boost Pumping Efficiency & Comfort BPA-Free Pump Essential for Moms**Nuliie**$9.90**445 rev5mo ago](https://www.amazon.com/dp/B0GJRV3N1Q) [![Nursi Luna Flange Sizing Kit with 13/15/17/19/21mm for 24mm Electric Breast Pump Flanges/Shields 10PCS Soft Silicone Flange Inserts for Enhanced Pumping Comfort BPA-Free Pump Essential for Moms](https://m.media-amazon.com/images/I/41PwwubUYYL.jpg)**Nursi Luna Flange Sizing Kit with 13/15/17/19/21mm for 24mm Electric Breast Pump Flanges/Shields 10PCS Soft Silicone Flange Inserts for Enhanced Pumping Comfort BPA-Free Pump Essential for Moms**Nursi Luna**$9.86**381 rev1y ago](https://www.amazon.com/dp/B0DT3QZ6Q2) [![Nursi Luna Flange Sizing Kit 3-in-1 with 13/15/17/19/21mm for 24mm Electric Breast Pump Flanges/Shields 10PCS Soft Silicone Flange Inserts for More Comfortable Pumping BPA-Free Essential for Moms](https://m.media-amazon.com/images/I/41TicDjnz7L.jpg)**Nursi Luna Flange Sizing Kit 3-in-1 with 13/15/17/19/21mm for 24mm Electric Breast Pump Flanges/Shields 10PCS Soft Silicone Flange Inserts for More Comfortable Pumping BPA-Free Essential for Moms**Nursi Luna**$9.87**2,081 rev2y ago](https://www.amazon.com/dp/B0CY81WHD5) [![Nursi Luna Flange Inserts 10PCS 13/15/17/19/21mm for 24mm Flanges/Shield of Most Pumps Flange Sizing Kit Silicone Flanges Insert Breastfeeding Essentials Kit for New Moms](https://m.media-amazon.com/images/I/415xYbVux6L.jpg)**Nursi Luna Flange Inserts 10PCS 13/15/17/19/21mm for 24mm Flanges/Shield of Most Pumps Flange Sizing Kit Silicone Flanges Insert Breastfeeding Essentials Kit for New Moms**Nursi Luna**$10.05**2,006 rev2y ago](https://www.amazon.com/dp/B0CKZH37FX) [![Nuliie 3-in-1 Flange Sizing Kit 13/15/17/19/21mm for 24mm Electric Double Breast Pump Flange/Shield 10PCS Silicone Flange Inserts to Boost Pumping Efficiency & Comfort BPA-Free Essential for Moms](https://m.media-amazon.com/images/I/41Feyi97wML.jpg)**Nuliie 3-in-1 Flange Sizing Kit 13/15/17/19/21mm for 24mm Electric Double Breast Pump Flange/Shield 10PCS Silicone Flange Inserts to Boost Pumping Efficiency & Comfort BPA-Free Essential for Moms**Nuliie**$9.68**4,179 rev2y ago](https://www.amazon.com/dp/B0CMPBBHMZ)

**~~View all new products →~~**

### **Trending**

90-day click momentum

[![Nuliie 5-in-1 Flange Sizing Kit 12/14/16/18/20mm for 24mm Flange/Shield of Most Pumps 10PCS Silicone Flange Inserts to Boost Pumping Efficiency & Comfort BPA-Free Pump Essential for Moms](https://m.media-amazon.com/images/I/51GT53yIMsL.jpg)**Nuliie 5-in-1 Flange Sizing Kit 12/14/16/18/20mm for 24mm Flange/Shield of Most Pumps 10PCS Silicone Flange Inserts to Boost Pumping Efficiency & Comfort BPA-Free Pump Essential for Moms**Nuliie**$9.90**4.5★**▲ 296%**](https://www.amazon.com/dp/B0GJRV3N1Q) [![Nursi Luna Flange Inserts 10PCS 13/15/17/19/21mm for 24mm Flanges/Shield of Most Pumps Flange Sizing Kit Silicone Flanges Insert Breastfeeding Essentials Kit for New Moms](https://m.media-amazon.com/images/I/415xYbVux6L.jpg)**Nursi Luna Flange Inserts 10PCS 13/15/17/19/21mm for 24mm Flanges/Shield of Most Pumps Flange Sizing Kit Silicone Flanges Insert Breastfeeding Essentials Kit for New Moms**Nursi Luna**$10.05**4.6★**▲ 71%**](https://www.amazon.com/dp/B0CKZH37FX) [![Flange Insert 13/15/17/19/21mm 10PCS Compatible with Momcozy S12 Pro/S9 Pro/S12/S9/Medela/Spectra etc Electric Breast Pump 24mm Flange/Shield Reduce 24mm Tunnel Down to Correct Size](https://m.media-amazon.com/images/I/41OcGg5lVUL.jpg)**Flange Insert 13/15/17/19/21mm 10PCS Compatible with Momcozy S12 Pro/S9 Pro/S12/S9/Medela/Spectra etc Electric Breast Pump 24mm Flange/Shield Reduce 24mm Tunnel Down to Correct Size**LOTBILL**$7.34**4.6★**▲ 23%**](https://www.amazon.com/dp/B0CL96VP1C) [![Flange Inserts 13/15/17/19/21mm 5pcs Suitable for Medela Spectra 24mm Shields/Flanges Compatible with Momcozy S12 Pro/S9 Pro/S9/S12 Wearable Breast Pump Reduce 24mm Tunnel Down to Correct Size](https://m.media-amazon.com/images/I/31RZ9-jx9hL.jpg)**Flange Inserts 13/15/17/19/21mm 5pcs Suitable for Medela Spectra 24mm Shields/Flanges Compatible with Momcozy S12 Pro/S9 Pro/S9/S12 Wearable Breast Pump Reduce 24mm Tunnel Down to Correct Size**GOCROWEEN**$8.01**4.4★**— 1%**](https://www.amazon.com/dp/B0BKH4TX4J) [![Nursi Luna Flange Sizing Kit with 13/15/17/19/21mm for 24mm Electric Breast Pump Flanges/Shields 10PCS Soft Silicone Flange Inserts for Enhanced Pumping Comfort BPA-Free Pump Essential for Moms](https://m.media-amazon.com/images/I/41PwwubUYYL.jpg)**Nursi Luna Flange Sizing Kit with 13/15/17/19/21mm for 24mm Electric Breast Pump Flanges/Shields 10PCS Soft Silicone Flange Inserts for Enhanced Pumping Comfort BPA-Free Pump Essential for Moms**Nursi Luna**$9.86**4.6★**▼ 17%**](https://www.amazon.com/dp/B0DT3QZ6Q2)

**~~View all trending →~~**

## **Demand & seasonality**

Weekly Amazon search volume, last 104 weeks — -9.1% search growth over the last 90 days.

18K13KSpike '24Spike '26 seasonSepDecMarJunAugNovMarMay

No pronounced peak months · busiest ÷ quietest = 1.3×

## **Reviews**

What buyers praise and complain about, mined from review topics.

### **What buyers love **

**Size-Overall**32%

*“Like the sizer”*

**Quality-Overall**13%

*“One thing that really stood out to me was how well-made”*

**Ease Of Use**10%

*“This made it so easy for me”*

**Value For Money**9%

*“Good price”*

**Comfort-Overall**8%

*“So comfortable”*

**Ease Of Cleaning**5%

*“The little cleaning sponge is wonderful”*

**Breastfeeding Friendly**4%

*“Very helpful and useful for breastfeeding”*

**Advertised Vs Actual Product**4%

*“It performs exactly as intended”*

**Compatibility-Overall**3%

*“Compatible with Frida Mom manual pump”*

**Durability**3%

*“durable”*

### **What buyers complain about **

**Size-Overall**32%

*“Does NOT fit”*

**Quality-Overall**7%

*“Poor quality”*

**Compatibility-Overall**6%

*“Incompatible with Elvie Stride”*

**Ease Of Cleaning**6%

*“they are kind of a pain to insert and clean and the output isnt as good as just using the correct size pump accessory”*

**Durability**6%

*“one of the flange inserts tore right apart immediately after opening”*

**Comfort-Overall**5%

*“Very uncomfortable”*

**Value For Money**4%

*“Waste of money”*

**Functionality-Overall**2%

*“Doesnt work for me”*

**Defective Material/Parts**2%

*“Horrible product, pieces missing, and some pieces broken”*

**Instructions/User Manual/Troubleshooting**2%

*“Instructions were not clear instead they were confusing”*

### **Top return reasons **

**Size-Overall**54%

**Functionality-Overall**9%

**Advertised Vs Actual Product**7%

**Defective Material/Parts**5%

**Material Quality**4%

**Comfort-Overall**3%

**Breastfeeding Friendly**3%

**Value For Money**3%

**Compatibility-Overall**2%

**Quality-Overall**2%