21mm Flange Insert
FailPrices span $6.92–$14.62, mostly outside the sweet spot, so 21mm Flange Insert is a Fail.
- Flapen Score
- 28 / 100Ranks 2,297 of 2,472 Baby Products niches · −16 vs the category median of 4428
- Market size
- $53K/yr40K searches / yr
- 90-day growth
- -7.5%search demand this quarter
- Competition
- 93%top-5 click share · 7 brands · 9 sellers
Flapen Score
21mm Flange Insert against its category
The dotted line is the Baby Products average. Past it, 21mm Flange Insert is stronger. Inside it, weaker.
Market
The 21mm Flange Insert market on Amazon at a glance
Shoppers on Amazon United States searched for 21mm Flange Insert 40K times last year and spent an estimated $53K. The top 5 brands take 93% of clicks. Flapen scores it 28 out of 100, a Fail.
01 · Demand
An estimated 14.6% of those searches ended in a purchase.
Shoppers searched for this 40K times in the last 12 months. That counts every search on Amazon United States for this niche's terms. An estimated 14.6% of those searches ended in a purchase. Searches in the last 90 days moved -7.5% against the 90 days before. Searches, conversion and average price together put the market at an estimated $53K a year.
- Searches, last 12 months
- 40K
- Growth, 90 days vs prior 90
- -7.5%
- Conversion, latest week
- 14.6%
- Market size, estimated
- $53Ka year
- Peak month
- July1.4× the quietest month
- Top search term
- 21mm flange insert22K searches a year
02 · Price
A sale here is worth $9.27.
Listings sell for $9.27 on average, from $6.92 to $14.62. Amazon reports units sold in ranges. This niche sold 6K to 8K a year. The average listing sells 500 to 750 of them. At $9.27 that is $5K to $7K a year per listing.
- Average price
- $9.27under the $15 to $100 sweet spot
- Price range
- $6.92–$14.62
- Amazon United States median price
- $24.38across 115,062 niches
- Units sold a year
- 6K–8K
- Units per listing a year
- 500–750
- Revenue per listing a year
- $5K–$7K
- Returns
- 4.8%of orders · Amazon United States median 2.1%
03 · Entry bar
The bar here is ads and reviews.
100% of listings pay for placement with sponsored ads. 100% ship with Prime. On an average day, 6.8% of listings are out of stock. The average listing ranks #36 within Breastfeeding. It carries 1,580 reviews at 4.53 stars, so a new listing needs social proof before a better product.
- Sponsored listings
- 100%
- Prime listings
- 100%
- Out of stock, average day
- 6.8%
- Average rank
- #36in Breastfeeding
- Average rating
- 4.53 starsAmazon United States average 4.42 stars
- Average reviews
- 1,580per listing
- Listings tracked
- 7
04 · Newcomers
Brands here are settling in.
The brands on the shelf have sold for 37 months on average, so the names here are settling in.
- Launched, last 12 months
- 0
- Successful launches
- 0Amazon's first-year sales bar
- Average brand age
- 37 months
Products
Top 21mm Flange Insert products & what they sell for
The products selling here, as shoppers see them on Amazon. Shelf share and sales are our estimates.
Prices and ratings read from Amazon on Jul 12, 2026. The live listing can differ.
Top sellers
by estimated 90-day click share
Flange Inserts 21mm Compatible with Medela/Spectra/TSRETE/Elvie/Momcozy/Bellababy Breast Pump 24mm Shields/Flanges Reduce 24mm Nipple Tunnel Down to 21 mm 4PCS
- Price
- $7.97
- Rating
- 4.5/5
- Reviews
- 971
- Age
- 2y ago

21mm Flange Insert 6PC Compatible with 21mm Flange Spectra/Flange Inserts for Spectra Flange 21mm/Momcozy Wearable Breast Pump Flange Insert/Medela Flange 21mm/Elvie/Willow/TSRETE
- Price
- $9.88
- Rating
- 4.5/5
- Reviews
- 562
- Age
- 2y ago

4Pcs Breast Pump Flange Insert 21mm Compatible with Momcozy/Spectra/Medela/eufy/Elvie/Lansinoh/Paruu P10 Breast Pump Fit for Momcozy M5/M9/M6/V2 Pro/V2 pro/S12 Pro/eufy E10 S1 S1 Pro 24mm Flange
- Price
- $7.84
- Rating
- 4.5/5
- Reviews
- 635
- Age
- 1y ago

Flange Inserts 21mm 8PC Compatible with Momcozy S12 pro/S9 pro/S9/S10/S12/Medela/TSRETE/Spectra/Bellababy etc 24mm Wearable Breast Pump Reduce 24mm Tunnel Down to Correct Size
- Price
- $7.96
- Rating
- 4.6/5
- Reviews
- 347
- Age
- 2y ago

Maymom Flange 21mm Insert Compatible with Medela/Spectra/Elvie/momcozy/tsrete/Willow/Motif Luna/Ameda MYA Breastpump 24mm Breast Shields. Reduce 24mm Niple Tunnel Down to 21mm
- Price
- $14.62
- Rating
- 4.5/5
- Reviews
- 3,517
- Age
- 3y ago
Trending
estimated 90-day click momentum
Flange Inserts 21mm 8PC Compatible with Momcozy S12 pro/S9 pro/S9/S10/S12/Medela/TSRETE/Spectra/Bellababy etc 24mm Wearable Breast Pump Reduce 24mm Tunnel Down to Correct Size
- Price
- $7.96
- Rating
- 4.6/5
- Reviews
- 347
- Age
- 2y ago

4Pcs Breast Pump Flange Insert 21mm Compatible with Momcozy/Spectra/Medela/eufy/Elvie/Lansinoh/Paruu P10 Breast Pump Fit for Momcozy M5/M9/M6/V2 Pro/V2 pro/S12 Pro/eufy E10 S1 S1 Pro 24mm Flange
- Price
- $7.84
- Rating
- 4.5/5
- Reviews
- 635
- Age
- 1y ago

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
- Price
- $9.68
- Rating
- 4.6/5
- Reviews
- 4,179
- Age
- 2y ago

21mm Flange Insert 6PC Compatible with 21mm Flange Spectra/Flange Inserts for Spectra Flange 21mm/Momcozy Wearable Breast Pump Flange Insert/Medela Flange 21mm/Elvie/Willow/TSRETE
- Price
- $9.88
- Rating
- 4.5/5
- Reviews
- 562
- Age
- 2y ago

Flange Inserts 21mm Compatible with Medela/Spectra/TSRETE/Elvie/Momcozy/Bellababy Breast Pump 24mm Shields/Flanges Reduce 24mm Nipple Tunnel Down to 21 mm 4PCS
- Price
- $7.97
- Rating
- 4.5/5
- Reviews
- 971
- Age
- 2y ago
Newest
by launch date
4Pcs Breast Pump Flange Insert 21mm Compatible with Momcozy/Spectra/Medela/eufy/Elvie/Lansinoh/Paruu P10 Breast Pump Fit for Momcozy M5/M9/M6/V2 Pro/V2 pro/S12 Pro/eufy E10 S1 S1 Pro 24mm Flange
- Price
- $7.84
- Rating
- 4.5/5
- Reviews
- 635
- Age
- 1y ago

IVARONAL Flange Insert 2PCS 21mm Compatible with Momcozy M9/M6/M5/S12 Pro/V1 Pro/V2 pro Spectra/Medela/Elvie/NCVI/TSRETE/eufy/Lansinoh/Paruu/MomMed Breast Pump 24mm Shields/Flanges (2pcs-21mm)
- Price
- $6.92
- Rating
- 4.5/5
- Reviews
- 848
- Age
- 2y ago

Flange Inserts 21mm Compatible with Medela/Spectra/TSRETE/Elvie/Momcozy/Bellababy Breast Pump 24mm Shields/Flanges Reduce 24mm Nipple Tunnel Down to 21 mm 4PCS
- Price
- $7.97
- Rating
- 4.5/5
- Reviews
- 971
- Age
- 2y ago

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
- Price
- $9.68
- Rating
- 4.6/5
- Reviews
- 4,179
- Age
- 2y ago

21mm Flange Insert 6PC Compatible with 21mm Flange Spectra/Flange Inserts for Spectra Flange 21mm/Momcozy Wearable Breast Pump Flange Insert/Medela Flange 21mm/Elvie/Willow/TSRETE
- Price
- $9.88
- Rating
- 4.5/5
- Reviews
- 562
- Age
- 2y ago
Competition
Competition: brands, sellers & click share
The top 5 products take an estimated 93% of clicks. A locked shelf that new listings rarely crack.
Brands
7 falling
Sellers
9
Est. top-5 brand share
93%
Top 20: 100%
Est. top-5 click share
93%
Top 20: 100%
Open market
3%
- Suniceme53%
- Hranio24%
- BDICOVE6%
- GOCROWEEN6%
- Maymom4%
- Nuliie4%
- Open — no brand owns it (1 brand, 3%)
Demand
21mm Flange Insert search demand
Weekly searches over the year, seasonality beneath. Pick a range.
No pronounced peak months · busiest ÷ quietest = 1.4×
Search terms
Top 21mm Flange Insert search terms shoppers use
The exact words shoppers type, with estimated yearly volume, growth, and conversion.
- 21mm flange insert22K/yr
- 21 mm flange insert14K/yr
- 21 flange inserts3K/yr
Reviews and returns
What reviews say buyers love and hate about 21mm Flange Insert
We read the reviews and the return reasons for every product selling here.
“Not true size”
Every topic
Every topic buyers talk about, one row each.
Red shows the share of negative reviews and green the share of positive reviews, biggest topic first. Open a row to read what they wrote.
17 topics
Keep looking
Related niches
Niches in the same category that score near this one. Research these next.
Best Flapen score
The highest-scoring niches we track right now, across every category.
FAQ
Common 21mm Flange Insert questions
Answered from the same tracked data.
Figures on this page are estimates modeled from public Amazon pages and third-party keyword data. Amazon does not supply them, and no connected seller's data is used. How we handle Amazon data









