head gasket test kit
Worth a lookShows beatable incumbent ratings (3.9★), but soft demand (-13.6% this quarter) keeps it on the watch list.
Quality gap
Incredible3.9★avg incumbent rating — lower means beatable quality
Conversion
Incredible12.7%search→purchase rate — share of searches ending in a sale
Returns
Great1.2%return rate — above 5% kills the launch gate
Avg price
Great£18.55avg listing price — sweet spot $15–$100
Price range
Great£10.87–£36.47cheapest to priciest tracked listing — scored on the share inside $15–$100
Review moat
Good868avg incumbent reviews — the moat a new listing must climb
Market size
Okay£118K£118K/yr · 50K searches
Brand share
Bad90%top-5 brand share — brand-locked demand
Competition
Bad78%top-5 click share — a locked-up shelf
Growth
Bad-13.6%90-day search growth — must beat 0% to launch
According to Flapen's Amazon United Kingdom niche tracking, head gasket test kit is a £118K/yr Amazon United Kingdom market (50K searches/yr). The top 5 brands hold 90% of demand. Verdict: Worth a look — 52/100.
Data updated Jul 18, 2026 · scored weekly · How we score niches
head gasket test kit market data
- Units sold / yr
- 4K–5K
- avg 250–500/product
- Revenue / yr
- £74K–£93K
- units × avg price
- Conversion rate
- 12.7%
- Avg BSR
- #120
- Page quality
- 0%
- Prime
- 100%
- Sponsored
- 80%
- Out of stock
- 0.0%
- Avg brand age
- 41 months
- Avg seller age
- 197 days
Competition & brand share
The top 5 products capture 78% of clicks — a locked-up shelf that new listings rarely crack.Brands
7 rising
Sellers
13
Top-5 brand share
90%
Top 20: 100%
Top-5 click share
78%
Top 20: 100%
Open market
4%
- RELD34%
- LeakLogic25%
- NoxGule14%
- AllisWay10%
- WEILAOK7%
- X6%
- Open — no brand owns it (1 brand, 4%)
Demand
Weekly Amazon search volume, last 28 weeks — -13.6% search growth over the last 90 days.Top head gasket test kit search terms
- head gasket test kit27K/yr
- head gasket tester10K/yr
- combustion leak tester kit7K/yr
- headgasket test kit6K/yr
Top head gasket test kit 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
RELD Cylinder Head Gasket Tester Kit CO2 Combustion Leak Gas Test Universal for All Cars and Motorcycles Petrol Diesel Block Rapid Engine Leak Detector for 50 Tests
RELD£18.654.5★7,797 rev
Block Check Blue Head Gasket Test Kit - Combustion Leak Detector & Engine Block Tester - CO2 Coolant Exhaust Gas Sniff Test for Cylinder Car Motorcycle Petrol & Diesel (Fluid Included 15 Tests)
LeakLogic£15.184.7★57 rev
AllisWay Head Gasket Test Kit Combustion Leak Tester Kit Head Gasket Tester Precise Detection Portable Operation Suitable For Car Truck Minibuse Transport Vehicle Motorcycle Detector for 50 Tests
AllisWay£10.873.3★10 rev
NoxGule Head Gasket Test Kit 100ml Head Gasket Tester Combustion Leak Tester Kit Precise Detection Universal Formula For Detecting Leaks in Motorcycle Diesel Engines Detector for 50 Tests - New
NoxGule£11.823.2★13 rev
NoxGule Head Gasket Test Kit Head Gasket Tester Combustion Leak Tester Kit Precise Detection Universal Formula For Detecting Leaks in Motorcycle Diesel Engines Easy to Use Detector for 50 Tests
NoxGule£12.313.7★29 rev
Newest
by launch dateAllisWay Head Gasket Test Kit Combustion Leak Tester Kit Head Gasket Tester Precise Detection Portable Operation Suitable For Car Truck Minibuse Transport Vehicle Motorcycle Detector for 50 Tests
AllisWay£10.8710 rev
NoxGule Head Gasket Test Kit 100ml Head Gasket Tester Combustion Leak Tester Kit Precise Detection Universal Formula For Detecting Leaks in Motorcycle Diesel Engines Detector for 50 Tests - New
NoxGule£11.8213 rev
WEILAOK Head Gasket Test Kit Head Gasket Tester Combustion Leak Tester Kit Includes Leak Detection Tool for Head Gasket Failure Engine Leak 100ml
WEILAOK£11.956 rev
NoxGule Head Gasket Test Kit Head Gasket Tester Combustion Leak Tester Kit Precise Detection Universal Formula For Detecting Leaks in Motorcycle Diesel Engines Easy to Use Detector for 50 Tests
NoxGule£12.3129 rev
WEILAOK Head Gasket Test Kit Head Gasket Tester Combustion Leak Tester Kit for Cars and Motorcycles Petrol Diesel Block Rapid Engine Leak Detector for 50 Tests
WEILAOK£14.8515 rev
Trending
90-day click momentumAllisWay Head Gasket Test Kit Combustion Leak Tester Kit Head Gasket Tester Precise Detection Portable Operation Suitable For Car Truck Minibuse Transport Vehicle Motorcycle Detector for 50 Tests
AllisWay£10.873.3★
NoxGule Head Gasket Test Kit 100ml Head Gasket Tester Combustion Leak Tester Kit Precise Detection Universal Formula For Detecting Leaks in Motorcycle Diesel Engines Detector for 50 Tests - New
NoxGule£11.823.2★
WEILAOK Head Gasket Test Kit Head Gasket Tester Combustion Leak Tester Kit Includes Leak Detection Tool for Head Gasket Failure Engine Leak 100ml
WEILAOK£11.952.9★
NoxGule Head Gasket Test Kit Head Gasket Tester Combustion Leak Tester Kit Precise Detection Universal Formula For Detecting Leaks in Motorcycle Diesel Engines Easy to Use Detector for 50 Tests
NoxGule£12.313.7★
Block Check Blue Head Gasket Test Kit - Combustion Leak Detector & Engine Block Tester - CO2 Coolant Exhaust Gas Sniff Test for Cylinder Car Motorcycle Petrol & Diesel (Fluid Included 15 Tests)
LeakLogic£15.184.7★
What buyers say about head gasket test kit
What buyers praise and complain about, mined from review topics.What buyers love
“Worked as stated”
“Easy to use”
“Good quality and performs exactly as it should”
“Good for the money”
“Does the job”
“Easy to use clear instructions”
“Worked well and detected a leak in my head gasket”
“a reliable indicator which saved me a trip to the mechanics”
“Quick answer to a costly repair”
“Helped me with diagnosing fluid in the engine oil”
What buyers complain about
“Does not function”
“Didnt change colour”
“If there are combustion gases leaking into your cooling system”
“Cheap and effective”
“Waste of money”
“Won't fit all radiators”
“Limited instructions on how to use”
“Product does not work even when held up to exhaust”
“I'm not sure if it's because of this extra viscosity”
“compression from the engine is lost either between cylinders”
Top return reasons
Common questions
- Is head gasket test kit profitable to sell on Amazon United Kingdom?
- The niche generates £118K/yr across 10 tracked products. 1 of 6 products launched in the last 360 days are still selling. 90-day search growth is -13.6%. Flapen's verdict: Worth a look (52/100).
- How competitive is the head gasket test kit niche?
- 7 brands and 13 sellers compete. The top 5 products take 78% of clicks and top 5 brands hold 90% of demand.
- What do buyers complain about in head gasket test kit?
- Top complaints mined from reviews: Functionality-Overall, Color, Leak-Proof. The return rate is 1.2%.
- What does it cost to enter the head gasket test kit niche?
- Listings span £10.87–£36.47; the average listing price is £18.55 (sweet spot $15–$100). The average incumbent carries 868 reviews — the moat a new listing must climb.