fiberglass resin hardener
Worth a lookShows low returns (0.3%), but a small market ($54K/yr) keeps it on the watch list.
Returns
Incredible0.3%return rate — above 5% kills the launch gate
Conversion
Great9.9%search→purchase rate — share of searches ending in a sale
Review moat
Great294.44avg incumbent reviews — the moat a new listing must climb
Avg price
Great$18.30avg listing price — sweet spot $15–$100
Price range
Great$4.02–$60.72cheapest to priciest tracked listing — scored on the share inside $15–$100
Growth
Good+30.7%90-day search growth — must beat 0% to launch
Brand share
Okay84%top-5 brand share — brands hold most of the demand
Quality gap
Bad4.6★avg incumbent rating — lower means beatable quality
Competition
Bad74%top-5 click share — a locked-up shelf
Market size
Bad$54K$54K/yr · 30K searches
According to Flapen's Amazon United States niche tracking, fiberglass resin hardener is a $54K/yr Amazon United States market (30K searches/yr). The top 5 brands hold 84% of demand. Verdict: Worth a look — 51/100.
Data updated Jul 8, 2026 · scored weekly · How we score niches
fiberglass resin hardener market data
- Units sold / yr
- 3K–4K
- avg 100–250/product
- Revenue / yr
- $55K–$73K
- units × avg price
- Conversion rate
- 9.9%
- Avg BSR
- #130
- Page quality
- 0%
- Prime
- 61%
- Sponsored
- 72%
- Out of stock
- 1.4%
- Avg brand age
- 71 months
- Avg seller age
- 178 days
Competition & brand share
The top 5 products capture 74% of clicks — a locked-up shelf that new listings rarely crack.Brands
12 flat
Sellers
76
Top-5 brand share
84%
Top 20: 100%
Top-5 click share
74%
Top 20: 100%
Open market
10%
- Fiberglass Supply Depot26%
- Polymer World18%
- FGCI16%
- Bondo16%
- Evercoat7%
- 3M6%
- Open — no brand owns it (6 brands, 10%)
Top fiberglass resin hardener search terms
- mekp catalyst10K/yr
- fiberglass resin hardener8K/yr
- mekp7K/yr
- fiberglass hardener5K/yr
Top fiberglass resin hardener 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 18 tracked products in this niche — three views at once, no toggling.
Top sellers
by 90-day click share
Fiberglass Supply Depot Clear Mek Peroxide Catalyst Hardener 4oz Bottle
Fiberglass Supply Depot$16.014.6★153 rev
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$4.024.7★657 rev
Polymer World MEKP 8oz - 236cc Clear Catalyst-Hardener for Polyester Resins Gelcoats Vinyl Esters Ceramic Transom Pour Includes 1oz Measuring Cup
Polymer World$24.954.7★78 rev
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$19.554.0★8 rev
Fiberglass Evercoat Liquid Hardener
Evercoat$13.034.8★305 rev
Newest
by launch date
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$15.03657 rev
Maven MEKP Liquid Catalyst 2 fl oz for Polyester and Vinyl Ester Resins (Organic Peroxide)
Maven$15.071 rev
J-B Weld Liquid Hardner - 0.74 Fl. Oz
J-B Weld$8.319 rev
Polymer World MEKP 8oz - 236cc Clear Catalyst-Hardener for Polyester Resins Gelcoats Vinyl Esters Ceramic Transom Pour Includes 1oz Measuring Cup
Polymer World$24.9578 rev
Polymer World- Premium Grade Polyester Resin 1-10 Gallon Kit with MEKP for Boats Cars Surfboard RV Pools Canoes Jetskis Watercrafts (1 1 Gallon)
Polymer World$44.50346 rev
Trending
90-day click momentum3M 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$15.034.7★
FGCI MEK-P CATALYST DISPENSER SQUEEZE BOTTLE Fiberglass Coatings Inc. THE PREMIUM MEKP SUPPLIER MEKP CATALYST HARDENER FOR POLYESTER RESIN & GELCOAT 16OZ
FGCI$10.204.5★
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$19.554.0★
LFI 50ml x 500ml Catalyst Dispenser Bottle Fiberglass Resin Adjustable Volume Dispenser
LFI$11.235.0★
Maven MEKP Liquid Catalyst 2 fl oz for Polyester and Vinyl Ester Resins (Organic Peroxide)
Maven$15.075.0★
What buyers say about fiberglass resin hardener
What buyers praise and complain about, mined from review topics.What buyers love
“Worked as Expected”
“Good product and easy to use”
“Good value”
“Works fine”
“Good product and easy to use”
“I like this resin”
“Chemical resistant and leak proof so far”
“it's held up great”
“Wvercoat compatibility”
What buyers complain about
“Leaked all over”
“Smells like you don't want to have around while it dries”
“This is very deceiving”
“Included directions were useless because the only instruction said to use the entire hardener with the entire gallon”
“Didn't work for my needs”
“Very small bottle”
“It's expensive for what it is”
“poor manufacturing”
“the box was wet”
“was a mess to deal with”
Top return reasons
Common questions
- Is fiberglass resin hardener profitable to sell on Amazon United States?
- The niche generates $54K/yr across 18 tracked products. 1 of 1 products launched in the last 360 days are still selling. 90-day search growth is +30.7%. Flapen's verdict: Worth a look (51/100).
- How competitive is the fiberglass resin hardener niche?
- 12 brands and 76 sellers compete. The top 5 products take 74% of clicks and top 5 brands hold 84% of demand.
- What do buyers complain about in fiberglass resin hardener?
- Top complaints mined from reviews: Leak-Proof, Smell, Advertised Vs Actual Product. The return rate is 0.3%.
- What does it cost to enter the fiberglass resin hardener niche?
- Listings span $4.02–$60.72; the average listing price is $18.30 (sweet spot $15–$100). The average incumbent carries 294 reviews — the moat a new listing must climb.