---
title: "stop leak — Niche Verdict: Skip it (40/100) | Amazon United States - Flapen"
canonical_url: "https://flapen.com/amazon/research/us/automotive/stop-leak"
last_updated: "2026-07-09T23:46:22.650Z"
locale: en
meta:
  description: "a concentrated shelf (top 5 take 86% of clicks) — stop leak doesn't clear our bar today."
  "og:description": "a concentrated shelf (top 5 take 86% of clicks) — stop leak doesn't clear our bar today."
  "og:title": "stop leak — Niche Verdict: Skip it (40/100) | Amazon United States - Flapen"
---

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# **stop leak**

**Skip it****40/100 **

a concentrated shelf (top 5 take 86% of clicks) — stop leak doesn't clear our bar today.

**Market/yr**

**$284K**

**Growth (1y)**

**+133.8%**

**Products**

**9**

**Brands**

**5**

was 8 a year ago

**Sellers**

**74**

**Price range**

**$4.10–$22.51**

**Returns**

**1.5%**

**Rating**

**4.4★**

**Skip it**

Scored 40/100 across market size, growth, competition, quality gap, and returns.

Market sizeGrowthCompetitionQuality gapReturns

Market size

**14**

 ×0.30

Growth

**69**

 ×0.30

Competition

**6**

 ×0.20

Quality gap

**53**

 ×0.10

Returns

**88**

 ×0.10

## **Demand**

Weekly Amazon search volume, last 104 weeks — +133.8% year over year.

6K3KSpike '25Jul '24Nov '24Mar '25Jul '25Nov '25Mar '26

## **Seasonality**

Monthly demand index across the year — 1.00 is average.

JFMAMJJASOND

Peak months: Aug · busiest ÷ quietest = 1.7×

## **Competition**

- K-Seal64% - Bar's Leaks25% - Liqui Moly5% - Visbella4% - ACDelco2%

The top 5 products capture 86% of clicks — a locked-up shelf that new listings rarely crack. 5 brands and 74 sellers compete here.

**Brands**

**5 **▼falling

was 8 a year ago

**Sellers**

**74**

**Top 5 brand share**

**100%**

#ProductBrandPriceRatingReviewsClick shareTrend

1
![K-Seal ST5501 Multi-Purpose One Step Coolant Leak Repair 8oz Pour and Go Mixes with All Antifreeze No Flushing Required](https://m.media-amazon.com/images/I/41KnvkA3vCL.jpg) [**K-Seal ST5501 Multi-Purpose One Step Coolant Leak Repair 8oz Pour and Go Mixes with All Antifreeze No Flushing Required**](https://www.amazon.com/dp/B001QT9KO6)

K-Seal$12.564.3★13,32343%▲rising

2
![Bars Leaks Cooling System Radiator Stop Leak 16.9 oz.](https://m.media-amazon.com/images/I/41lyX-fz8mS.jpg) [**Bars Leaks Cooling System Radiator Stop Leak 16.9 oz.**](https://www.amazon.com/dp/B002696FA2)

Bar's Leaks$7.774.3★3,82017%▲rising

3
![K-Seal ST5516 Heavy-Duty Multi-Purpose One Step Coolant Leak Repair 16 oz Pour and Go Mixes with All Antifreeze No Flushing Required](https://m.media-amazon.com/images/I/41iccT7xXWL.jpg) [**K-Seal ST5516 Heavy-Duty Multi-Purpose One Step Coolant Leak Repair 16 oz Pour and Go Mixes with All Antifreeze No Flushing Required**](https://www.amazon.com/dp/B002BJEG3U)

K-Seal$20.274.4★1,66514%▼falling

4
![K-Seal ST3501 Pour & Go Head Gasket Sealer 16 oz Repairs Blown Head Gaskets Cracked Heads & Engine Blocks](https://m.media-amazon.com/images/I/31+ZGzaDiLL.jpg) [**K-Seal ST3501 Pour & Go Head Gasket Sealer 16 oz Repairs Blown Head Gaskets Cracked Heads & Engine Blocks**](https://www.amazon.com/dp/B00QYZIVA6)

K-Seal$22.514.1★2,1097%▼falling

5
![Bars Leaks 1109 Liquid Copper Block Seal Intake and Radiator Stop Leak 18 oz. | One Step Safe for All Cooling Systems](https://m.media-amazon.com/images/I/41RujwLzvuL.jpg) [**Bars Leaks 1109 Liquid Copper Block Seal Intake and Radiator Stop Leak 18 oz. | One Step Safe for All Cooling Systems**](https://www.amazon.com/dp/B002PX91OG)

Bar's Leaks$8.074.3★1,5066%▼falling

6
![Liqui Moly Radiator Stop Leak | 250 ml | Cooler additive | SKU: 20132](https://m.media-amazon.com/images/I/31Vo7sEGrAL.jpg) [**Liqui Moly Radiator Stop Leak | 250 ml | Cooler additive | SKU: 20132**](https://www.amazon.com/dp/B076ZP45Z5)

Liqui Moly$12.754.4★6555%▲rising

7
![Visbella Radiator Stop Leak Sealer Conditioner Radiator Repair Kit Car Heater Core Freeze Plugs Cooling System & Radiator Repair (Tube pcs 1)](https://m.media-amazon.com/images/I/41S2ow5I6WL.jpg) [**Visbella Radiator Stop Leak Sealer Conditioner Radiator Repair Kit Car Heater Core Freeze Plugs Cooling System & Radiator Repair (Tube pcs 1)**](https://www.amazon.com/dp/B0D1B7Z26G)

Visbella$8.064.5★1544%—flat

8
![Bars Leaks Radiator Stop Leak 11 oz](https://m.media-amazon.com/images/I/41RucpeZdEL.jpg) [**Bars Leaks Radiator Stop Leak 11 oz**](https://www.amazon.com/dp/B0CLB9NGG3)

Bar's Leaks$4.994.4★2323%▼falling

9
![ACDelco GM Original Equipment 10-108 (12378255) Cooling System Sealing Tabs - 4 g (Pack of 5)](https://m.media-amazon.com/images/I/31-VbvMrrXL.jpg) [**ACDelco GM Original Equipment 10-108 (12378255) Cooling System Sealing Tabs - 4 g (Pack of 5)**](https://www.amazon.com/dp/B0026JK8C8)

ACDelco$4.104.6★1,3052%▼falling

## **Product shelf**

All 9 tracked products in this niche.

Top sellersNewestTrending

[![K-Seal ST5501 Multi-Purpose One Step Coolant Leak Repair 8oz Pour and Go Mixes with All Antifreeze No Flushing Required](https://m.media-amazon.com/images/I/41KnvkA3vCL.jpg)**K-Seal ST5501 Multi-Purpose One Step Coolant Leak Repair 8oz Pour and Go Mixes with All Antifreeze No Flushing Required** K-Seal**$12.56**4.3★13,323 reviews](https://www.amazon.com/dp/B001QT9KO6) [![Bars Leaks Cooling System Radiator Stop Leak 16.9 oz.](https://m.media-amazon.com/images/I/41lyX-fz8mS.jpg)**Bars Leaks Cooling System Radiator Stop Leak 16.9 oz.** Bar's Leaks**$7.77**4.3★3,820 reviews](https://www.amazon.com/dp/B002696FA2) [![K-Seal ST5516 Heavy-Duty Multi-Purpose One Step Coolant Leak Repair 16 oz Pour and Go Mixes with All Antifreeze No Flushing Required](https://m.media-amazon.com/images/I/41iccT7xXWL.jpg)**K-Seal ST5516 Heavy-Duty Multi-Purpose One Step Coolant Leak Repair 16 oz Pour and Go Mixes with All Antifreeze No Flushing Required** K-Seal**$20.27**4.4★1,665 reviews](https://www.amazon.com/dp/B002BJEG3U) [![K-Seal ST3501 Pour & Go Head Gasket Sealer 16 oz Repairs Blown Head Gaskets Cracked Heads & Engine Blocks](https://m.media-amazon.com/images/I/31+ZGzaDiLL.jpg)**K-Seal ST3501 Pour & Go Head Gasket Sealer 16 oz Repairs Blown Head Gaskets Cracked Heads & Engine Blocks** K-Seal**$22.51**4.1★2,109 reviews](https://www.amazon.com/dp/B00QYZIVA6) [![Bars Leaks 1109 Liquid Copper Block Seal Intake and Radiator Stop Leak 18 oz. | One Step Safe for All Cooling Systems](https://m.media-amazon.com/images/I/41RujwLzvuL.jpg)**Bars Leaks 1109 Liquid Copper Block Seal Intake and Radiator Stop Leak 18 oz. | One Step Safe for All Cooling Systems** Bar's Leaks**$8.07**4.3★1,506 reviews](https://www.amazon.com/dp/B002PX91OG) [![Liqui Moly Radiator Stop Leak | 250 ml | Cooler additive | SKU: 20132](https://m.media-amazon.com/images/I/31Vo7sEGrAL.jpg)**Liqui Moly Radiator Stop Leak | 250 ml | Cooler additive | SKU: 20132** Liqui Moly**$12.75**4.4★655 reviews](https://www.amazon.com/dp/B076ZP45Z5) [![Visbella Radiator Stop Leak Sealer Conditioner Radiator Repair Kit Car Heater Core Freeze Plugs Cooling System & Radiator Repair (Tube pcs 1)](https://m.media-amazon.com/images/I/41S2ow5I6WL.jpg)**Visbella Radiator Stop Leak Sealer Conditioner Radiator Repair Kit Car Heater Core Freeze Plugs Cooling System & Radiator Repair (Tube pcs 1)** Visbella**$8.06**4.5★154 reviews](https://www.amazon.com/dp/B0D1B7Z26G) [![Bars Leaks Radiator Stop Leak 11 oz](https://m.media-amazon.com/images/I/41RucpeZdEL.jpg)**Bars Leaks Radiator Stop Leak 11 oz** Bar's Leaks**$4.99**4.4★232 reviews](https://www.amazon.com/dp/B0CLB9NGG3)

## **Reviews**

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

### **What buyers love **

**Leak-Proof**26%

*“Stop leak”*

**Efficiency**15%

*“Works well”*

**Value For Money**11%

*“Worth the purchase”*

**Quality-Overall**11%

*“quality are all good”*

**Advertised Vs Actual Product**7%

*“Works as advertised”*

**Coolant**5%

*“Stopped my coolant leak”*

**Ease Of Use**3%

*“Easy peasy”*

**Instructions/User Manual/Troubleshooting**3%

*“Followed the directions”*

**Maintenance And Repair**2%

*“that it would not affect the repair”*

**Durability**2%

*“its still holding”*

### **What buyers complain about **

**Leak-Proof**32%

*“Had a leak”*

**Functionality-Overall**16%

*“Did not work”*

**Coolant**9%

*“If you have a slight loss of coolant or a head gasket that is just starting to leak”*

**Maintenance And Repair**5%

*“Repairs are ridiculous”*

**Heating**4%

*“Car started overheating again”*

**Jamming/Clogging**3%

*“clogs”*

**Instructions/User Manual/Troubleshooting**3%

*“Lasted exactly 7 miles when followed directions exactly ending in large fail”*

**Value For Money**2%

*“which is expensive ($4500 quoted for my last car).”*

**Quality-Overall**2%

*“Trash”*

**Durability**2%

*“Does not last”*

#### **Top return reasons**- Leak-Proof20% - Coolant19% - Functionality-Overall16% - Compatibility-Overall10% - Maintenance And Repair7% - Defective Material/Parts6% - Value For Money6% - Advertised Vs Actual Product5% - Product Condition3% - Size-Overall2%