Is 16mm flange inserts profitable to sell on Amazon United States?

The niche generates $171K/yr across 24 tracked products. 2 of 5 products launched in the last 360 days are still selling. 90-day search growth is -2.5%. Flapen's verdict: Skip it (42/100).

How competitive is the 16mm flange inserts niche?

12 brands and 15 sellers compete. The top 5 products take 65% of clicks and top 5 brands hold 88% of demand.

What do buyers complain about in 16mm flange inserts?

Top complaints mined from reviews: Size-Overall, Durability, Quality-Overall. The return rate is 4.9%.

When does demand for 16mm flange inserts peak?

Demand peaks in Jun; the busiest month runs 1.7× the quietest.

What does it cost to enter the 16mm flange inserts niche?

Listings span $6.90–$32.43; the average listing price is $13.28 (sweet spot $15–$100). The average incumbent carries 2,404 reviews — the moat a new listing must climb.

16mm flange inserts

Skip it

Soft demand (-2.5% this quarter) — this niche doesn't clear our bar today.

Conversion

Incredible16.2%

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

Price range

Good$6.90–$32.43

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

Avg price

Good$13.28

avg listing price — sweet spot $15–$100

Quality gap

Okay4.5★

avg incumbent rating — lower means beatable quality

Review moat

Okay2,404.33

avg incumbent reviews — the moat a new listing must climb

Market size

Okay$171K

$171K/yr · 80K searches

Competition

Okay65%

top-5 click share — leaders hold, buyers still browse

Brand share

Okay88%

top-5 brand share — brands hold most of the demand

Returns

Okay4.9%

return rate — above 5% kills the launch gate

Growth

Bad-2.5%

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

According to Flapen's Amazon United States niche tracking, 16mm flange inserts is a $171K/yr Amazon United States market (80K searches/yr). The top 5 brands hold 88% of demand. Demand peaks in Jun. Verdict: Skip it — 42/100.

Data updated Jul 12, 2026 · scored weekly · How we score niches

16mm flange inserts market data

Units sold / yr: 13K–15K; avg 500–750/product
Revenue / yr: $166K–$199K; units × avg price
Conversion rate: 16.2%
Avg BSR: #63
Page quality: 0%
Prime: 100%
Sponsored: 79%
Out of stock: 0.0%
Avg brand age: 33 months
Avg seller age: 161 days

Competition & brand share

The top 5 products take 65% of clicks — established leaders, but buyers still shop beyond them.

Brands

12 rising

Sellers

Top-5 brand share

88%

Top 20: 100%

Top-5 click share

65%

Top 20: 96%

Open market

Maymom32%
BDICOVE23%
TOVVILD14%
Momstouch13%
IVARONAL5%
Nuliie3%
Open — no brand owns it (6 brands, 9%)

Demand & seasonality

Weekly Amazon search volume, last 103 weeks — -2.5% search growth over the last 90 days.

Peak months: Jun · busiest ÷ quietest = 1.7×

Open Trend

Top 16mm flange inserts search terms

16mm flange inserts18K/yr -6.7%14.6% conv.
16 mm flange insert15K/yr +3.4%15.6% conv.
16mm flange spectra11K/yr -12.2%13.7% conv.
spectra flange 16mm9K/yr -3.8%16.6% conv.
spectra 16mm flange6K/yr +3.8%18.0% conv.
16 mm flange spectra6K/yr -4.4%16.5% conv.
16mm flange5K/yr -5.3%12.2% conv.
size 16 flange insert3K/yr +20.9%16.7% conv.
16 mm flange3K/yr +7.8%10.6% conv.
spectra 16 mm flange set3K/yr +2.8%16.6% conv.

All search terms

Top 16mm flange inserts products on Amazon

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

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

All 24 tracked products in this niche — three views at once, no toggling.

Top sellers

by 90-day click share

4Pcs Breast Pump Flange Insert 16mm 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

BDICOVE$7.914.5★635 rev

Maymom 16mm Flange and Duckbill Valve Compatible with Spectra S1 Spectra S2 Spectra 9 Plus Not Original Spectra Pump Parts Replace Spectra S2 Pump Parts Spectra Flange Spectra Duckbill Valve

Maymom$19.594.6★6,022 rev

TOVVILD 16mm Flange Inserts for 24mm Flange/Shield Compatible with Momcozy/Medela/MOMMED/Spectra Breast Pumps Pump Parts Replace (4PCS 16mm)

TOVVILD$8.894.4★1,539 rev

Maymom 16mm Wide Neck Pump Part for Spectra S1/S2 Pumps; Compatible with Motif Luna Pump; Incl Wide Mouth Flange; Not Original Spectra Flange

Maymom$17.614.7★7,932 rev

Momstouch 16mm Flange and Duckbill Valve Compatible with Spectra S1 S2 9 Plus Breastpump Replacement to Spectra Pump Parts Not Original Replace Accessories.

Momstouch$16.744.3★592 rev

Newest

by launch date

Spectra - Wide Breast Shield Set for Breast Milk Pump - XS 16mm

SPECTRA$29.441,312 rev

4mo ago

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$9.90445 rev

5mo ago

2PC Flange Insert 16mm Compatible with Momcozy Air 1/W1/M9/M6/M5/V1 Pro/V2 Pro for Spectra/eufy/Medela/Elvie/Lansinoh/Paruu with 24mm Flange/Shield Pump Pumping Essentials Flange Insert Kits

Wevedk$6.9063 rev

8mo ago

6pcs Updated Silicone Flange Insert 16mm Compatible with Momcozy/Medela/Spectra/Eufy/Lansinoh/TSRETE/Elvie/NCVI/Paruu Breast Pump for 24mm Flange/Shield Breastfeeding Essential Replacement Pump Part

BDICOVE$9.91169 rev

10mo ago

MOOMentaneous 16mm Oval Flanges Breast Pump Parts Compatible with Medela Breast Pumps PersonalFit Maxflow Freestyle Flex Swing Maxi Connector

MOOMentaneous$12.61207 rev

11mo ago

What buyers say about 16mm flange inserts

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

What buyers love

Size-Overall31%

“fits comfortably for me”

Quality-Overall15%

“Overall, the parts themselves seem great and the quality feels solid”

Value For Money8%

“Great price”

Advertised Vs Actual Product8%

“Exactly What I Needed”

Ease Of Cleaning7%

“The little cleaning sponge is wonderful”

Comfort-Overall6%

“are very comfy”

Compatibility-Overall4%

“Everything fits well with my Spectra pump”

Ease Of Use4%

“was easy to use”

Durability4%

“durable”

Breastfeeding Friendly4%

“Very helpful and useful for breastfeeding”

What buyers complain about

Size-Overall25%

“These are huge”

Durability12%

“that broke within a few uses”

Quality-Overall8%

“Poor quality”

Value For Money6%

“These were not cheap to buy”

Thickness6%

“The flange part is a bit thin”

Compatibility-Overall4%

“These don't work with the Elvie”

Functionality-Overall4%

“Doesnt work for me”

Instructions/User Manual/Troubleshooting4%

“fewer manuals would be a less frustrating customer experience”

Ease Of Use3%

“Semi-useful”

Adhesion/Stickiness3%

“Too sticky; nipple can move”

Top return reasons

Size-Overall70%

Advertised Vs Actual Product5%

Functionality-Overall5%

Defective Material/Parts3%

Material Quality3%

Width2%

Value For Money2%

Breastfeeding Friendly2%

Compatibility-Overall1%

Comfort-Overall1%

Common questions

Is 16mm flange inserts profitable to sell on Amazon United States?: The niche generates $171K/yr across 24 tracked products. 2 of 5 products launched in the last 360 days are still selling. 90-day search growth is -2.5%. Flapen's verdict: Skip it (42/100).
How competitive is the 16mm flange inserts niche?: 12 brands and 15 sellers compete. The top 5 products take 65% of clicks and top 5 brands hold 88% of demand.
What do buyers complain about in 16mm flange inserts?: Top complaints mined from reviews: Size-Overall, Durability, Quality-Overall. The return rate is 4.9%.
When does demand for 16mm flange inserts peak?: Demand peaks in Jun; the busiest month runs 1.7× the quietest.
What does it cost to enter the 16mm flange inserts niche?: Listings span $6.90–$32.43; the average listing price is $13.28 (sweet spot $15–$100). The average incumbent carries 2,404 reviews — the moat a new listing must climb.