brake fluid cap
Skip itPrices mostly outside the sweet spot ($4.59–$16.31) — this niche doesn't clear our bar today.
Quality gap
Incredible3.7★avg incumbent rating — lower means beatable quality
Review moat
Great130.12avg incumbent reviews — the moat a new listing must climb
Brand share
Great57%top-5 brand share — no brand owns this niche
Conversion
Good6.1%search→purchase rate — share of searches ending in a sale
Competition
Good54%top-5 click share — leaders hold, buyers still browse
Avg price
Bad$8.11avg listing price — sweet spot $15–$100
Growth
Bad-7.3%90-day search growth — must beat 0% to launch
Returns
Bad7.4%return rate — above 5% kills the launch gate
Market size
Bad$53K$53K/yr · 106K searches
Price range
Bad$4.59–$16.31cheapest to priciest tracked listing — scored on the share inside $15–$100
According to Flapen's Amazon United States niche tracking, brake fluid cap is a $53K/yr Amazon United States market (106K searches/yr). The top 5 brands hold 57% of demand. Verdict: Skip it — 45/100.
Data updated Jul 9, 2026 · scored weekly · How we score niches
brake fluid cap market data
- Units sold / yr
- 5K–6K
- avg 100–250/product
- Revenue / yr
- $41K–$49K
- units × avg price
- Conversion rate
- 6.1%
- Avg BSR
- #233
- Page quality
- 0%
- Prime
- 100%
- Sponsored
- 28%
- Out of stock
- 1.8%
- Avg brand age
- 35 months
- Avg seller age
- 195 days
Competition & brand share
The top 5 products take 54% of clicks — established leaders, but buyers still shop beyond them.Brands
20 falling
Sellers
66
Top-5 brand share
57%
Top 20: 100%
Top-5 click share
54%
Top 20: 94%
Open market
38%
- QQWD30%
- ESWW10%
- Motorcraft6%
- pvotawp6%
- YUPIKJI5%
- AUPARTIK5%
Demand & seasonality
Weekly Amazon search volume, last 104 weeks — -7.3% search growth over the last 90 days.No pronounced peak months · busiest ÷ quietest = 1.3×
Top brake fluid cap search terms
- brake fluid reservoir cap17K/yr
- brake fluid cap25K/yr
- master cylinder cap17K/yr
- brake reservoir cap17K/yr
- brake fluid cap replacement12K/yr
- brake master cylinder cap10K/yr
- brake master cylinder reservoir cap6K/yr
- brake cap4K/yr
Top brake fluid cap 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 24 tracked products in this niche — three views at once, no toggling.
Top sellers
by 90-day click share
Brake Fluid Cap Replacement OEM #4683656AB 5014518AA Brake Master Cylinder Cap Compatible with 2001-2017 Jeep Wrangler 2009-2020 Dodge Journey 2014-2020 Cherokee 2017-2020 Brake Fluid Reservoir Caps
QQWD$6.852.5★134 rev
ESWW Dot 3 Brake Fluid Cap Replacement 20760280 Brake Master Cylinder Reservoir Cap for Cadillac Escalade ESV Chevy Suburban Tahoe Silverado Volt GMC Yukon Sierra Acadia Canyon Buick Enclave Lucerne
ESWW$9.254.6★24 rev
PVOTAWP Brake Fluid Cap Replacement for Honda Brake Master Cylinder Tank Fluid Reservoir Cap Compatible with Honda Accord Fit EV Hybrid S2000 Accessories 46662-SLE-J01 46662-SDC-A02 46662-S8A-003
pvotawp$8.384.5★127 rev
Brake Fluid Cap Replacement OEM#4683656AB Brake Master Cylinder Cap Compatible with Chrysler Sebring Dodge Ram 1500 2500 3500 Jeep Wrangler JK Standard Brake Reservoir Cap
carleef$5.524.7★81 rev
Motorcraft - Cap - Filler (P) (BRFC21)
Motorcraft$16.314.7★89 rev
Newest
by launch date
CouTunp Brake Fluid Cap Yellow Brake Master Cylinder Fluid Reservoir Cap Car Brake Master Cylinder Cap Compatible with Jeep Wrangler Compass Cherokee Chrysler Replaces 68303540AA 68211910AB
CouTunp$9.511 rev
ESWW Dot 3 Brake Fluid Cap Replacement 20760280 Brake Master Cylinder Reservoir Cap for Cadillac Escalade ESV Chevy Suburban Tahoe Silverado Volt GMC Yukon Sierra Acadia Canyon Buick Enclave Lucerne
ESWW$9.2524 rev
Brake Fluid Cap Brake Master Cylinder Cap Master Cylinder Tank Fluid Reservoir Cover Compatible with Honda Accord Fit EV Hybrid Replace OEM# 46662-SLE-J01 46662-SDC-A02 46662-S8A-003
YUPIKJI$7.593 rev
JYIS 1PC Brake Master Cylinder Cap Cylinder Tank Reservoir Cap Replacement Replaces OEM# 46662-SLE-J01 46662-SDC-A02 46662-S8A-003 Car Brake Fluid Cap Accessories Compatible with Honda Accord CR-V
JYIS$6.327 rev
Icyfond Brake Fluid Cap Brake Master Cylinder Reservoir Cap Brake Oil tank Cap OEM#68211910AB Compatible with Wrangler Cherokee Compass Chrysler Pacifica(Yellow)
Icyfond$8.935 rev
Trending
90-day click momentum
WZP Brake Fluid Cap Master Cylinder Fluid Cap with Built-in Rubber Sealing Ring Brake Reservoir Replacement Compatible with Honda Accord Replaces for 46662-SLE-J01 46662-SDC-A02 46662-S8A-003
WZP$6.591.8★
CouTunp Brake Fluid Cap Yellow Brake Master Cylinder Fluid Reservoir Cap Car Brake Master Cylinder Cap Compatible with Jeep Wrangler Compass Cherokee Chrysler Replaces 68303540AA 68211910AB
CouTunp$9.511.0★
Icyfond Brake Fluid Cap Brake Master Cylinder Reservoir Cap Brake Oil tank Cap OEM#68211910AB Compatible with Wrangler Cherokee Compass Chrysler Pacifica(Yellow)
Icyfond$8.934.0★
YUPIKJI Brake Fluid Cap Brake Reservoir Cap Master Cylinder Filler Caps Replace OEM #4683656AB 5014518AA Car Accessories Fluid Tank Reservoir Cover Compatible with Dodge Jeep Chrysler Ram Dakota
YUPIKJI$6.113.9★
ESWW Dot 3 Brake Fluid Cap Replacement 20760280 Brake Master Cylinder Reservoir Cap for Cadillac Escalade ESV Chevy Suburban Tahoe Silverado Volt GMC Yukon Sierra Acadia Canyon Buick Enclave Lucerne
ESWW$9.254.6★
What buyers say about brake fluid cap
What buyers praise and complain about, mined from review topics.What buyers love
“Fit like it should”
“Performs as it should”
“it's worth every penny”
“OEM-Quality Fit: It threaded on smoothly”
“Cap worked great”
“Does not leak”
“The part was perfect”
“A++ As good as factory - No compliants”
“Durable Build: The plastic feels thick, rugged, and heat-resistant, so I expect it to hold up well under under-hood temperatures for a long time”
“seems to be made of quality materials”
What buyers complain about
“DOES NOT FIT”
“Doesn't fit all cars”
“Wrong description”
“If youre dealing with a leaking or damaged cap”
“Not universal”
“Coolant cap cracked tightening it down on 2017 f250 super duty”
“Didnt fit what they said it would I have a 2011 Mercedes 2500 sprinter van the filter said it would fit”
“It isn't even good quality”
“Waste of money- do not buy”
“Waste of money”
Top return reasons
Common questions
- Is brake fluid cap profitable to sell on Amazon United States?
- The niche generates $53K/yr across 25 tracked products. 1 of 11 products launched in the last 360 days are still selling. 90-day search growth is -7.3%. Flapen's verdict: Skip it (45/100).
- How competitive is the brake fluid cap niche?
- 20 brands and 66 sellers compete. The top 5 products take 54% of clicks and top 5 brands hold 57% of demand.
- What do buyers complain about in brake fluid cap?
- Top complaints mined from reviews: Size-Overall, Compatibility-Overall, Advertised Vs Actual Product. The return rate is 7.4% — above our launch gate.
- When does demand for brake fluid cap peak?
- Demand is steady year-round — the busiest month runs 1.3× the quietest.
- What does it cost to enter the brake fluid cap niche?
- Listings span $4.59–$16.31; the average listing price is $8.11 (sweet spot $15–$100). The average incumbent carries 130 reviews — the moat a new listing must climb.