19mm flange
Skip itBrand-locked demand (top 5 brands take 97% of clicks) — this niche doesn't clear our bar today.
Conversion
Great10.1%search→purchase rate — share of searches ending in a sale
Avg price
Great$17.16avg listing price — sweet spot $15–$100
Price range
Good$8.00–$32.53cheapest to priciest tracked listing — scored on the share inside $15–$100
Market size
Good$513K$513K/yr · 298K searches
Quality gap
Okay4.5★avg incumbent rating — lower means beatable quality
Competition
Okay64%top-5 click share — leaders hold, buyers still browse
Returns
Okay4.8%return rate — above 6% kills the launch gate
Review moat
Okay3,967.11avg incumbent reviews — the moat a new listing must climb
Growth
Bad-16.8%90-day search growth — must beat 0% to launch
Brand share
Bad97%top-5 brand share — brand-locked demand
Competition
The top 5 products take 64% of clicks — established leaders, but buyers still shop beyond them.Brands
7 rising
Sellers
9
Top-5 brand share
97%
Open market
2%
- Maymom77%
- Hranio8%
- Momstouch6%
- CubCare3%
- PUMPMOM-US2%
- BALIME2%
- Open — no brand owns it (1 brand, 2%)
Product shelf
Each bubble is one product — market share against review moat; bubble size tracks estimated sales, color grades how beatable the incumbent looks.
All 19 tracked products in this niche — three views at once, no toggling.
Top sellers
by 90-day click share
Maymom 19mm Flange and Duckbill Valve Compatible with Spectra S1 S2 Breastpump Not Original S2 Accessories Not Original Spectra Replacement Duckbill Valve and Flange
Maymom$18.754.6★6,022 rev
Maymom Pump Parts Compatible with Spectra S2 S1 Replacement Kit for Spectra Pump Parts 24 mm Flange Duckbill Valve Tube Bottle Backflow Protector Not Original S2 S1 Accessories
Maymom$32.534.6★9,124 rev
Maymom Wide Neck Pump Part Compatible with Spectra S1/S2 Pumps; Incl Wide Mouth Flange; Not Original Spectra Flange; Replaces Shield (19 mm Two Flanges)
Maymom$16.634.7★7,932 rev
17mm Maymom MyFit Shields Pano Series; Compatible with Medela Breast Pump- PersonalFit Freestyle Harmony Maxi Freestyle Flex Connector; Connect to Maymom Widemouth/Narrow Connector 2pcs
Maymom$15.534.5★8,889 rev
Hranio Breast Pump Parts Compatible with 19mm Spectra Flange 19mm Spectra Replacement Pump Parts s1 s2 (Flange 19mm 2 Pcs)
Hranio$9.834.5★217 rev
Newest
by launch date
BALIME 19MM Wide-Mouth Flange Spectra Replacement Pump Parts for S1 S2 - BPA Free Spectra Replacement Pump Parts - Perfect for Travel & Working Moms (2-Pack)
BALIME$8.25129 rev
Flange Inserts for Spectra Spectra Replacement Pump Parts for S1/S2/9 Plus Not Original Accessories Breast Pump Parts Include 2-Pack 19MM Flanges and 4-Pack Duckbill Valves
CubCare$9.74119 rev
Hranio Breast Pump Parts Compatible with 19mm Spectra Flange 19mm Spectra Replacement Pump Parts s1 s2 (Flange 19mm 2 Pcs)
Hranio$9.83217 rev
PumpMom-us 19mm Soft Rim Flanges Compatible with Spectra S2 S1 9 Plus Breastpumps Accessories Replacement Breast Shield and Duckbill Valves for Spectra Pump Parts and 19 Flange
PUMPMOM-US$16.80915 rev
Flange Inserts 19mm Compatible with Medela/Spectra/TSRETE/Elvie/Momcozy/Bellababy Breast Pump 24mm Shields/Flanges Reduce 24mm Nipple Tunnel Down to 19 mm 4PCS
Suniceme$8.00971 rev
Trending
90-day click momentum
Momstouch 19mm Flange Compatible with Spectra S1 S2 9 Plus Synergy Gold Breastpump Replacement to Spectra Pump Parts and Flange; Not Original; Replaces Shield
Momstouch$15.674.6★
BALIME 19MM Wide-Mouth Flange Spectra Replacement Pump Parts for S1 S2 - BPA Free Spectra Replacement Pump Parts - Perfect for Travel & Working Moms (2-Pack)
BALIME$8.254.4★
Momstouch 19mm Flange and Duckbill Valve Compatible with Spectra S1 S2 9 Plus Breastpump Replacement to Spectra Pump Parts Not Original Replace Accessories.
Momstouch$16.714.3★
PumpMom-us 19mm Soft Rim Flanges Compatible with Spectra S2 S1 9 Plus Breastpumps Accessories Replacement Breast Shield and Duckbill Valves for Spectra Pump Parts and 19 Flange
PUMPMOM-US$16.804.4★
Maymom 19mm MyFit Shields Pano Series; Compatible with Medela Breast Pump- PersonalFit Freestyle Harmony Maxi Freestyle Flex Connector; Connect to Maymom Widemouth/Narrow Connector 2pcs
Maymom$15.494.5★
Demand & seasonality
Weekly Amazon search volume, last 103 weeks — -16.8% search growth over the last 90 days.Peak months: Jan · busiest ÷ quietest = 1.9×
Reviews
What buyers praise and complain about, mined from review topics.What buyers love
“Fit me and the pump”
“Worth it”
“High quality loved the storage case”
“they work great with mine”
“does what it is intended to do”
“So comfortable”
“Easy to clean”
“the parts are easy to wash”
“I used them throughout my pumping, and they worked great, no issues, and came clean easily with Dawn soap, even when there was coconut oil or nipple cream on the flanges”
“Easy to use, easy to clean in electric sterile and dryer”
What buyers complain about
“Way too big”
“the flanges did not seem like they should have made it past quality control”
“pretty useless when the bottles dont really connect”
“Breaks easily”
“Did not work”
“Seems to be this flange is defective”
“imo these are basically $20 trash not $40 worth of savings. actual spectra parts I think are like $60”
“are flimsy and will not work”
“Arrived used”
“When you first start using the adaptors this will feel impossible”