valve
Skip itA concentrated shelf (top 5 take 85% of clicks) — this niche doesn't clear our bar today.
Avg price
Great$17.79avg listing price — sweet spot $15–$100
Price range
Great$9.68–$41.19cheapest to priciest tracked listing — scored on the share inside $15–$100
Returns
Good2.2%return rate — above 5% kills the launch gate
Quality gap
Good4.4★avg incumbent rating — lower means beatable quality
Conversion
Good4.4%search→purchase rate — share of searches ending in a sale
Review moat
Okay2,815.7avg incumbent reviews — the moat a new listing must climb
Market size
Okay$168K$168K/yr · 213K searches
Growth
Bad-24.9%90-day search growth — must beat 0% to launch
Brand share
Bad95%top-5 brand share — brand-locked demand
Competition
Bad85%top-5 click share — a locked-up shelf
According to Flapen's Amazon United States niche tracking, valve is a $168K/yr Amazon United States market (213K searches/yr). The top 5 brands hold 95% of demand. Demand peaks in Jan–Jun. Verdict: Skip it — 39/100.
Data updated Jul 12, 2026 · scored weekly · How we score niches
valve market data
- Units sold / yr
- 4K–5K
- avg 250–500/product
- Revenue / yr
- $71K–$89K
- units × avg price
- Conversion rate
- 4.4%
- Avg BSR
- #71
- Page quality
- 0%
- Prime
- 100%
- Sponsored
- 100%
- Out of stock
- 0.0%
- Avg brand age
- 42 months
- Avg seller age
- 139 days
Competition & brand share
The top 5 products capture 85% of clicks — a locked-up shelf that new listings rarely crack.Brands
7 rising
Sellers
13
Top-5 brand share
95%
Top 20: 100%
Top-5 click share
85%
Top 20: 100%
Open market
3%
- Legendairy Milk65%
- Nursi Luna11%
- Momcozy8%
- Elvie7%
- Nuliie4%
- Mompmuir3%
- Open — no brand owns it (1 brand, 3%)
Demand & seasonality
Weekly Amazon search volume, last 104 weeks — -24.9% search growth over the last 90 days.Peak months: Jan, Jun · busiest ÷ quietest = 2.0×
Top valve search terms
- legendary milk flange inserts66K/yr
- legendairy milk inserts35K/yr
- legendairy flange inserts31K/yr
- legendairy milk flanges13K/yr
- legendairy milk flange insert25K/yr
- legendairy milk duckbill valves10K/yr
- legendary flange inserts9K/yr
- legendairy milk flange inserts5K/yr
- legendary milk duckbill valves6K/yr
- legendary milk inserts5K/yr
Top valve 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.
All 10 tracked products in this niche — three views at once, no toggling.
Top sellers
by 90-day click share
Legendairy Milk Duckbill Valves with Pull Tab - Compatible with Spectra S1 S2 9 Plus Medela Motif Baby Buddha & Zomee - Duckbill Valve Replacement Pump Parts BPA Free Silicone 6 Pack
Legendairy Milk$11.764.4★1,673 rev

Legendairy Milk Pumping Spray 4 oz. Helps Sore Nipples & Clogged Ducts Organic Lubricant for Breast Shields and Flanges Vegan Breast Pump Spray Natural & Lanolin-Free Made in USA
Legendairy Milk$24.774.5★1,557 rev

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$10.054.6★2,006 rev

Momcozy 999 Silver Nursing Cups Original Perforated Breathable Design 999 Silver Nipple Cover for Breastfeeding Essential Nipple Shield for Nursing Newborn Metal Nipple Shields Regular Size
Momcozy$41.194.3★691 rev

Elvie Nipple Cushions 17mm | Soft-Silicone Nipple Cushions to Enhance fit for Improved Comfort and Efficiency (2 Pack)
Elvie$20.204.2★486 rev
Newest
by launch date
Momcozy 999 Silver Nursing Cups Original Perforated Breathable Design 999 Silver Nipple Cover for Breastfeeding Essential Nipple Shield for Nursing Newborn Metal Nipple Shields Regular Size
Momcozy$41.19691 rev

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$9.872,081 rev

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$10.052,006 rev

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$9.684,179 rev

Legendairy Milk Pumping Spray 4 oz. Helps Sore Nipples & Clogged Ducts Organic Lubricant for Breast Shields and Flanges Vegan Breast Pump Spray Natural & Lanolin-Free Made in USA
Legendairy Milk$24.771,557 rev
Trending
90-day click momentum
Momcozy 999 Silver Nursing Cups Original Perforated Breathable Design 999 Silver Nipple Cover for Breastfeeding Essential Nipple Shield for Nursing Newborn Metal Nipple Shields Regular Size
Momcozy$41.194.3★

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$10.054.6★

Durceler 17mm Silicone Flange Inserts Compatible with Medela/for Spectra S1 S2 / Elvie / S18 S21 / Momcozy S9 S12/ TSRETE 24mm Breast Pump Shields or Freemie 25mm; Reduce Nipple Tunnel Down to 17mm
Durceler$14.594.2★

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$9.684.6★

Legendairy Milk Liquid Gold Lactation Support | Lactation Supplement with Organic Goats Rue Milk Thistle Shatavari Fennel Alfalfa & Anise | Breastfeeding Supplements 1 Pack
Legendairy Milk$21.184.1★
What buyers say about valve
What buyers praise and complain about, mined from review topics.What buyers love
“The best sizing kit”
“Good quality”
“Easy to take”
“Lactation support”
“So comfortable”
“Good value for money”
“its been such a lifesaver for keeping clean”
“they are pretty durable”
“Love the color”
“It performs exactly as intended”
What buyers complain about
“Didn't work”
“Not worth it”
“These are huge”
“They all leak”
“Poor Quality”
“Very uncomfortable”
“stomach pain Ive ever had”
“when I was drying them after a clean they bent easily”
“baby very gassy”
“Doesn't have a taste”
Top return reasons
Common questions
- Is valve profitable to sell on Amazon United States?
- The niche generates $168K/yr across 10 tracked products. 90-day search growth is -24.9%. Flapen's verdict: Skip it (39/100).
- How competitive is the valve niche?
- 7 brands and 13 sellers compete. The top 5 products take 85% of clicks and top 5 brands hold 95% of demand.
- What do buyers complain about in valve?
- Top complaints mined from reviews: Functionality-Overall, Value For Money, Size-Overall. The return rate is 2.2%.
- When does demand for valve peak?
- Demand peaks in Jan–Jun; the busiest month runs 2.0× the quietest.
- What does it cost to enter the valve niche?
- Listings span $9.68–$41.19; the average listing price is $17.79 (sweet spot $15–$100). The average incumbent carries 2,816 reviews — the moat a new listing must climb.