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radiator flush kit

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Soft demand (-14.0% this quarter) — this niche doesn't clear our bar today.

Market size 20Growth 18Conversion 42Competition 50Returns 54Price range 87Avg price 95Brand share 73Review moat 46Quality gap 50

Avg price

Incredible$25.85

avg listing price — sweet spot $15–$100

Price range

Great$5.82–$93.11

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

Brand share

Good61%

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

Returns

Good2.8%

return rate — above 6% kills the launch gate

Competition

Good55%

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

Quality gap

Good4.5★

avg incumbent rating — lower means beatable quality

Review moat

Okay1,856.04

avg incumbent reviews — the moat a new listing must climb

Conversion

Okay3.4%

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

Market size

Bad$82K

$82K/yr · 94K searches

Growth

Bad-14.0%

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

Competition

The top 5 products take 55% of clicks — established leaders, but buyers still shop beyond them.

Brands

18 falling

Sellers

71

Top-5 brand share

61%

Open market

34%

  • Dorman17%
  • EPAuto13%
  • QUFYSK12%
  • SEDY10%
  • Prestone9%
  • SMART JERRY5%

Product shelf

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

0%5%$4K10%$8K15%$12K20%$16K1101001K10K100K Reviews — right = deep review moat Market share (90d) ≈ est. sales
Beatable (≤4.3★) Contested Strong incumbent (>4.7★)

All 23 tracked products in this niche — three views at once, no toggling.

Demand & seasonality

Weekly Amazon search volume, last 104 weeks — -14.0% search growth over the last 90 days.
2K2KSpike '25SepDecMarJunAugNovMarMay

No pronounced peak months · busiest ÷ quietest = 1.2×

Reviews

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

What buyers love

Quality-Overall19%

“Excellent quality product”

Ease Of Use10%

“Pretty handy”

Coolant9%

“worked well for my coolant change”

Value For Money9%

“Great deal”

Efficiency9%

“Working good”

Leak-Proof8%

“Did not leak”

Advertised Vs Actual Product8%

“As advertised”

Size-Overall4%

“Excellent fit”

Ease Of Cleaning3%

“No messes”

Heating2%

“heat is now acceptable”

What buyers complain about

Compatibility-Overall20%

“Pieces are not compatible”

Leak-Proof16%

“Leaks from EVERYWHERE”

Quality-Overall9%

“Cheap quality”

Size-Overall9%

“Not large enough”

Coolant4%

“coolant was drain”

Heating2%

“weeks after today it overheat”

Functionality-Overall2%

“if it does not work as planned”

Instructions/User Manual/Troubleshooting2%

“Directions are poor”

Rusts/Corrodes2%

“it quickly became contaminated with rust also”

Material Quality2%

“it is made of very weak plastic”

Top return reasons

Size-Overall25%
Compatibility-Overall17%
Coolant13%
Leak-Proof8%
Defective Material/Parts7%
Functionality-Overall6%
Advertised Vs Actual Product5%
Value For Money4%
Add-Ons/Attachments2%
Product Condition2%