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title: "fiberglass resin hardener — Niche Verdict: Skip it (40/100) | Amazon United States - Flapen"
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  description: "a small market ($54K/yr) — fiberglass resin hardener doesn't clear our bar today."
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# **fiberglass resin hardener**

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

a small market ($54K/yr) — fiberglass resin hardener doesn't clear our bar today.

**Market/yr**

**$54K**

**Growth (1y)**

**+163.5%**

**Products**

**18**

**Brands**

**12**

was 12 a year ago

**Sellers**

**76**

**Price range**

**$4.02–$60.72**

**Returns**

**0.3%**

**Rating**

**4.6★**

**Skip it**

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

Market sizeGrowthCompetitionQuality gapReturns

Market size

**3**

 ×0.30

Growth

**72**

 ×0.30

Competition

**25**

 ×0.20

Quality gap

**29**

 ×0.10

Returns

**98**

 ×0.10

## **Competition**

- Fiberglass Supply Depot26% - Polymer World18% - FGCI16% - Bondo16% - Evercoat7% - 3M6% - Other (6 brands)10%

The top 5 products capture 74% of clicks — a locked-up shelf that new listings rarely crack. 12 brands and 76 sellers compete here.

**Brands**

**12 **—flat

was 12 a year ago

**Sellers**

**76**

**Top 5 brand share**

**84%**

#ProductBrandPriceRatingReviewsClick shareTrend

1
![Fiberglass Supply Depot Clear Mek Peroxide Catalyst Hardener 4oz Bottle](https://m.media-amazon.com/images/I/31ab3D1y2mL.jpg) [**Fiberglass Supply Depot Clear Mek Peroxide Catalyst Hardener 4oz Bottle**](https://www.amazon.com/dp/B08PMVK4DR)

Fiberglass Supply Depot$16.014.6★15319%▼falling

2
![3M Bondo Liquid Hardener 1 Tube 0.37 fl oz. Use with Fiberglass Resin for Auto and Home Repairs Including Tubs Showers Sinks Pools Hot Tubs and Boats Waterproof Repair (00912)](https://m.media-amazon.com/images/I/31b-PIVguDL.jpg) [**3M Bondo Liquid Hardener 1 Tube 0.37 fl oz. Use with Fiberglass Resin for Auto and Home Repairs Including Tubs Showers Sinks Pools Hot Tubs and Boats Waterproof Repair (00912)**](https://www.amazon.com/dp/B000BO6RUC)

Bondo$4.024.7★65716%▼falling

3
![Polymer World MEKP 8oz - 236cc Clear Catalyst-Hardener for Polyester Resins Gelcoats Vinyl Esters Ceramic Transom Pour Includes 1oz Measuring Cup](https://m.media-amazon.com/images/I/31zpYGlczoL.jpg) [**Polymer World MEKP 8oz - 236cc Clear Catalyst-Hardener for Polyester Resins Gelcoats Vinyl Esters Ceramic Transom Pour Includes 1oz Measuring Cup**](https://www.amazon.com/dp/B0CV6WY1K7)

Polymer World$24.954.7★7816%▼falling

4
![FGCI Boatyard Polyester Laminating Resin 1 Quart Kit with MEKP Hardener Clear Fiberglass Resin for Boat Repair and Small Layup Projects Made in the USA](https://m.media-amazon.com/images/I/310EFAbRw5L.jpg) [**FGCI Boatyard Polyester Laminating Resin 1 Quart Kit with MEKP Hardener Clear Fiberglass Resin for Boat Repair and Small Layup Projects Made in the USA**](https://www.amazon.com/dp/B006VY78QS)

FGCI$19.554.0★815%▲rising

5
![Fiberglass Evercoat Liquid Hardener](https://m.media-amazon.com/images/I/519OnCxqErL.jpg) [**Fiberglass Evercoat Liquid Hardener**](https://www.amazon.com/dp/B000SMB25W)

Evercoat$13.034.8★3057%▼falling

6
![3M Bondo Liquid Hardener 1 Tube 0.37 fl oz. Use with Fiberglass Resin for Auto and Home Repairs Including Tubs Showers Sinks Pools Hot Tubs and Boats Waterproof Repair (00912) 4-Pack](https://m.media-amazon.com/images/I/51pIfFUpgAL.jpg) [**3M Bondo Liquid Hardener 1 Tube 0.37 fl oz. Use with Fiberglass Resin for Auto and Home Repairs Including Tubs Showers Sinks Pools Hot Tubs and Boats Waterproof Repair (00912) 4-Pack**](https://www.amazon.com/dp/B0GTG3MGCY)

3M$15.034.7★6574%▲rising

7
![Fiberglass Supply Depot MEKP Dispensing Bottle 500ML (16oz)](https://m.media-amazon.com/images/I/210smT4FRCL.jpg) [**Fiberglass Supply Depot MEKP Dispensing Bottle 500ML (16oz)**](https://www.amazon.com/dp/B078TPPXH1)

Fiberglass Supply Depot$15.914.4★4224%▼falling

8
![Maven MEKP Liquid Catalyst 2 fl oz for Polyester and Vinyl Ester Resins (Organic Peroxide)](https://m.media-amazon.com/images/I/31jocj5GJZL.jpg) [**Maven MEKP Liquid Catalyst 2 fl oz for Polyester and Vinyl Ester Resins (Organic Peroxide)**](https://www.amazon.com/dp/B0FBPDKJCB)

Maven$15.075.0★13%▲rising

9
![Polymer World- Premium Grade Polyester Resin 1-10 Gallon Kit with MEKP for Boats Cars Surfboard RV Pools Canoes Jetskis Watercrafts (1 1 Gallon)](https://m.media-amazon.com/images/I/410VI8dzBRL.jpg) [**Polymer World- Premium Grade Polyester Resin 1-10 Gallon Kit with MEKP for Boats Cars Surfboard RV Pools Canoes Jetskis Watercrafts (1 1 Gallon)**](https://www.amazon.com/dp/B0C7CZ2644)

Polymer World$44.504.7★3462%▲rising

10

![J-B Weld Liquid Hardner - 0.74 Fl. Oz](https://m.media-amazon.com/images/I/41WVTZNZloL.jpg) [**J-B Weld Liquid Hardner - 0.74 Fl. Oz**](https://www.amazon.com/dp/B0DQTR8PRW)

J-B Weld$8.315.0★92%▼falling

11

![LFI 50ml x 500ml Catalyst Dispenser Bottle Fiberglass Resin Adjustable Volume Dispenser](https://m.media-amazon.com/images/I/419wFENWL7L.jpg) [**LFI 50ml x 500ml Catalyst Dispenser Bottle Fiberglass Resin Adjustable Volume Dispenser**](https://www.amazon.com/dp/B07BR831SX)

LFI$11.235.0★112%▲rising

12

![TotalBoat Polyester Laminating Resin - Marine Grade Fiberglass Resin and MEKP Catalyst for Layups and Repairs (Gallon)](https://m.media-amazon.com/images/I/41TnwqE9NML.jpg) [**TotalBoat Polyester Laminating Resin - Marine Grade Fiberglass Resin and MEKP Catalyst for Layups and Repairs (Gallon)**](https://www.amazon.com/dp/B00PZ09NMQ)

TotalBoat$60.724.6★1,1742%▼falling

13

![Fiberglass Supply Depot Mek Peroxide Catalyst 60cc Clear](https://m.media-amazon.com/images/I/31G4y-zWVaL.jpg) [**Fiberglass Supply Depot Mek Peroxide Catalyst 60cc Clear**](https://www.amazon.com/dp/B08PL1JBFP)

Fiberglass Supply Depot$14.974.7★462%▼falling

14

![FGCI MEK-P CATALYST DISPENSER SQUEEZE BOTTLE Fiberglass Coatings Inc. THE PREMIUM MEKP SUPPLIER MEKP CATALYST HARDENER FOR POLYESTER RESIN & GELCOAT 16OZ](https://m.media-amazon.com/images/I/31VE1mZn-BL.jpg) [**FGCI MEK-P CATALYST DISPENSER SQUEEZE BOTTLE Fiberglass Coatings Inc. THE PREMIUM MEKP SUPPLIER MEKP CATALYST HARDENER FOR POLYESTER RESIN & GELCOAT 16OZ**](https://www.amazon.com/dp/B01FY9UR04)

FGCI$10.204.5★992%▲rising

15

![3M Bondo Fiberglass Resin 0.9 Pint Stage 2 Waterproof Formula for Repairing Resurfacing or Rebuilding Metal Wood Fiberglass or Masonry Surfaces (401)](https://m.media-amazon.com/images/I/316Lvn3rzWL.jpg) [**3M Bondo Fiberglass Resin 0.9 Pint Stage 2 Waterproof Formula for Repairing Resurfacing or Rebuilding Metal Wood Fiberglass or Masonry Surfaces (401)**](https://www.amazon.com/dp/B0002KKIZ0)

3M$20.514.6★6761%▼falling

**~~Showing 15 of 18 — show all ~~**

## **Product shelf**

All 18 tracked products in this niche.

Top sellersNewestTrending

[![Fiberglass Supply Depot Clear Mek Peroxide Catalyst Hardener 4oz Bottle](https://m.media-amazon.com/images/I/31ab3D1y2mL.jpg)**Fiberglass Supply Depot Clear Mek Peroxide Catalyst Hardener 4oz Bottle** Fiberglass Supply Depot**$16.01**4.6★153 reviews](https://www.amazon.com/dp/B08PMVK4DR) [![3M Bondo Liquid Hardener 1 Tube 0.37 fl oz. Use with Fiberglass Resin for Auto and Home Repairs Including Tubs Showers Sinks Pools Hot Tubs and Boats Waterproof Repair (00912)](https://m.media-amazon.com/images/I/31b-PIVguDL.jpg)**3M Bondo Liquid Hardener 1 Tube 0.37 fl oz. Use with Fiberglass Resin for Auto and Home Repairs Including Tubs Showers Sinks Pools Hot Tubs and Boats Waterproof Repair (00912)** Bondo**$4.02**4.7★657 reviews](https://www.amazon.com/dp/B000BO6RUC) [![Polymer World MEKP 8oz - 236cc Clear Catalyst-Hardener for Polyester Resins Gelcoats Vinyl Esters Ceramic Transom Pour Includes 1oz Measuring Cup](https://m.media-amazon.com/images/I/31zpYGlczoL.jpg)**Polymer World MEKP 8oz - 236cc Clear Catalyst-Hardener for Polyester Resins Gelcoats Vinyl Esters Ceramic Transom Pour Includes 1oz Measuring Cup** Polymer World**$24.95**4.7★78 reviews](https://www.amazon.com/dp/B0CV6WY1K7) [![FGCI Boatyard Polyester Laminating Resin 1 Quart Kit with MEKP Hardener Clear Fiberglass Resin for Boat Repair and Small Layup Projects Made in the USA](https://m.media-amazon.com/images/I/310EFAbRw5L.jpg)**FGCI Boatyard Polyester Laminating Resin 1 Quart Kit with MEKP Hardener Clear Fiberglass Resin for Boat Repair and Small Layup Projects Made in the USA** FGCI**$19.55**4.0★8 reviews](https://www.amazon.com/dp/B006VY78QS) [![Fiberglass Evercoat Liquid Hardener](https://m.media-amazon.com/images/I/519OnCxqErL.jpg)**Fiberglass Evercoat Liquid Hardener** Evercoat**$13.03**4.8★305 reviews](https://www.amazon.com/dp/B000SMB25W) [![3M Bondo Liquid Hardener 1 Tube 0.37 fl oz. Use with Fiberglass Resin for Auto and Home Repairs Including Tubs Showers Sinks Pools Hot Tubs and Boats Waterproof Repair (00912) 4-Pack](https://m.media-amazon.com/images/I/51pIfFUpgAL.jpg)**3M Bondo Liquid Hardener 1 Tube 0.37 fl oz. Use with Fiberglass Resin for Auto and Home Repairs Including Tubs Showers Sinks Pools Hot Tubs and Boats Waterproof Repair (00912) 4-Pack** 3M**$15.03**4.7★657 reviews](https://www.amazon.com/dp/B0GTG3MGCY) [![Fiberglass Supply Depot MEKP Dispensing Bottle 500ML (16oz)](https://m.media-amazon.com/images/I/210smT4FRCL.jpg)**Fiberglass Supply Depot MEKP Dispensing Bottle 500ML (16oz)** Fiberglass Supply Depot**$15.91**4.4★422 reviews](https://www.amazon.com/dp/B078TPPXH1) [![Maven MEKP Liquid Catalyst 2 fl oz for Polyester and Vinyl Ester Resins (Organic Peroxide)](https://m.media-amazon.com/images/I/31jocj5GJZL.jpg)**Maven MEKP Liquid Catalyst 2 fl oz for Polyester and Vinyl Ester Resins (Organic Peroxide)** Maven**$15.07**5.0★1 reviews](https://www.amazon.com/dp/B0FBPDKJCB)

## **Reviews**

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

### **What buyers love **

**Advertised Vs Actual Product**23%

*“Worked as Expected”*

**Quality-Overall**22%

*“Good product and easy to use”*

**Value For Money**17%

*“Good value”*

**Efficiency**10%

*“Works fine”*

**Ease Of Use**9%

*“Good product and easy to use”*

**Material Quality**5%

*“I like this resin”*

**Leak-Proof**3%

*“Chemical resistant and leak proof so far”*

**Durability**2%

*“it's held up great”*

**Compatibility-Overall**2%

*“Wvercoat compatibility”*

### **What buyers complain about **

**Leak-Proof**34%

*“Leaked all over”*

**Smell**9%

*“Smells like you don't want to have around while it dries”*

**Advertised Vs Actual Product**8%

*“This is very deceiving”*

**Instructions/User Manual/Troubleshooting**6%

*“Included directions were useless because the only instruction said to use the entire hardener with the entire gallon”*

**Functionality-Overall**6%

*“Didn't work for my needs”*

**Size-Overall**6%

*“Very small bottle”*

**Value For Money**6%

*“It's expensive for what it is”*

**Quality-Overall**6%

*“poor manufacturing”*

**Moist/Dry**3%

*“the box was wet”*

**Ease Of Cleaning**2%

*“was a mess to deal with”*

#### **Top return reasons**- Leak-Proof77% - Size-Overall7% - Defective Material/Parts4% - Advertised Vs Actual Product4% - Adhesion/Stickiness3% - Compatibility-Overall1% - Value For Money1% - Material Quality1% - Ease Of Cleaning1% - Water Resistance1%