---
product_id: 267575393
title: "Clear Mek Peroxide Catalyst Hardener 4oz Bottle"
brand: "fiberglass supply depot"
price: "$U1833"
currency: UYU
in_stock: true
reviews_count: 8
category: "Fiberglass Supply Depot"
url: https://www.desertcart.uy/products/267575393-clear-mek-peroxide-catalyst-hardener-4oz-bottle
store_origin: UY
region: Uruguay
---

# fast curing catalyst 4oz precision dosing multi-surface compatibility Clear Mek Peroxide Catalyst Hardener 4oz Bottle

**Brand:** fiberglass supply depot
**Price:** $U1833
**Availability:** ✅ In Stock

## Summary

> ⚡ Cure it fast, craft it flawless — your secret weapon in composite mastery!

## Quick Answers

- **What is this?** Clear Mek Peroxide Catalyst Hardener 4oz Bottle by fiberglass supply depot
- **How much does it cost?** $U1833 with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.uy](https://www.desertcart.uy/products/267575393-clear-mek-peroxide-catalyst-hardener-4oz-bottle)

## Best For

- fiberglass supply depot enthusiasts

## Why This Product

- Trusted fiberglass supply depot brand quality
- Free international shipping included
- Worldwide delivery with tracking
- 15-day hassle-free returns

## Key Features

- • **Trusted by Pros:** Preferred by composite experts for consistent performance across industrial and hobbyist projects.
- • **Mix with Confidence:** Includes measuring cup and ratio guide to ensure perfect catalyst-to-resin balance every time.
- • **Precision 4oz Bottle:** Compact size for controlled, waste-free application on small to medium projects.
- • **Rapid Resin Activation:** Kickstarts polyester and gelcoat curing fast for dependable, professional-grade results.
- • **Versatile Composite Use:** Perfect for marine, automotive, surfboards, tooling, and general fiberglass fabrication.

## Overview

Clear Mek Peroxide Catalyst Hardener is a 4oz liquid MEKP catalyst designed to accelerate curing in polyester resins, vinyl ester resins, and gelcoat systems. Ideal for fiberglass repairs, marine maintenance, and composite fabrication, it offers precise dosing with an included measuring cup and ratio guide. Trusted by professionals and DIYers alike, it ensures fast, reliable hardening for durable, high-quality finishes.

## Description

Fiberglass Supply Depot Clear Mek Peroxide Catalyst Hardener 4oz Bottle: desertcart.com: Industrial & Scientific

Review: Great for DIY Plastic Projects - I’ve been using this MEK Peroxide Catalyst for some DIY hobby projects, mainly to fuse plastic sheets and small pieces together, and it’s worked really well. The durability of the bond it creates is better than I expected. Once it cures, the pieces stay tight and clean. The functionality is exactly what I needed. It reacts fast and gives a strong hold, especially when paired with a syringe-style applicator, which makes the ease of use even better. Just make sure to apply slowly and precisely. For the price, the value for money is great. A little goes a long way, and the results are consistent. One thing to note is to use it in a well-ventilated space, since it’s strong stuff and you don’t want to breathe it in. Overall, it’s a reliable catalyst that performs the way it should and is perfect for plastic-related DIY work.
Review: Wvercoat compatibility - Great product. Works well with Wvercoat have gh strength fiberglass epoxy.

## Features

- MEKP CATALYST FOR POLYESTER RESIN & GELCOAT – Clear liquid methyl ethyl ketone peroxide (MEKP) catalyst designed for use with polyester resins, vinyl ester resins, and gelcoat systems in fiberglass fabrication, repair, and composite manufacturing applications.
- VERSATILE COMPOSITE APPLICATIONS – Commonly used for fiberglass repairs, boat building, marine maintenance, mold making, automotive composites, surfboard construction, tooling, and general composite fabrication projects.
- PROMOTES PROPER RESIN CURING – Helps initiate the curing process when used according to resin manufacturer recommendations, supporting consistent hardening and dependable results across a variety of fiberglass and composite applications.
- COMPACT 4 OZ BOTTLE – Ideal size for small repairs, maintenance work, hobby projects, prototype fabrication, and shop use where a smaller quantity of catalyst is preferred for controlled dispensing and storage.
- INCLUDES MEASURING CUP & MIX RATIO GUIDE – Comes with a reusable measuring cup and MEKP catalyst percentage chart to simplify mixing. The included 4 oz bottle provides enough catalyst to cure approximately 4 gallons of polyester resin or gelcoat when used at a 1% catalyst ratio, helping reduce waste and improve mixing accuracy for fiberglass and composite projects.
- TRUSTED BY COMPOSITE PROFESSIONALS – Suitable for marine, automotive, industrial, and general fiberglass applications. Packaged by Fiberglass Supply Depot, a trusted supplier serving fiberglass and composite customers

## Technical Specifications

| Specification | Value |
|---------------|-------|
| ASIN | B08PMVK4DR |
| Best Sellers Rank | #20,310 in Industrial & Scientific ( See Top 100 in Industrial & Scientific ) #85 in Commercial All-Purpose Cleaners |
| Brand | Fiberglass Supply Depot |
| Brand Name | Fiberglass Supply Depot |
| Color | Clear |
| Customer Reviews | 4.6 out of 5 stars 159 Reviews |
| Grade Rating | Commercial/Industrial |
| Item Form | Liquid |
| Item Shape | Flat |
| Item Weight | 4 ounces |
| Manufacturer | Fiberglass Supply Depot Inc. |
| Material | mek peroxide |
| Number of Items | 1 |
| Part Number | mek4ozb |
| Shape | Flat |
| Specification Met | True |
| UPC | 819794022743 |
| Unit Count | 4 Fluid Ounces |

## Product Details

- **Brand:** Fiberglass Supply Depot
- **Color:** Clear
- **Item Form:** Liquid
- **Material:** mek peroxide
- **Shape:** Flat

## Images

![Clear Mek Peroxide Catalyst Hardener 4oz Bottle - Image 1](https://m.media-amazon.com/images/I/61lBjlpGhgL.jpg)
![Clear Mek Peroxide Catalyst Hardener 4oz Bottle - Image 2](https://m.media-amazon.com/images/I/61hibaEJzdL.jpg)
![Clear Mek Peroxide Catalyst Hardener 4oz Bottle - Image 3](https://m.media-amazon.com/images/I/81d+nrrNVtL.jpg)
![Clear Mek Peroxide Catalyst Hardener 4oz Bottle - Image 4](https://m.media-amazon.com/images/I/81OdcnXI7-L.jpg)
![Clear Mek Peroxide Catalyst Hardener 4oz Bottle - Image 5](https://m.media-amazon.com/images/I/81fr-++BOcL.jpg)

## Questions & Answers

**Q: shelf life?**
A: It has a shelf life of 7 months but anything over 90 days I would do a test because shelf life can vary depending on how it is stored. Heat is not its friend.

## Customer Reviews

### ⭐⭐⭐⭐⭐ Great for DIY Plastic Projects
*by P***E on December 5, 2025*

I’ve been using this MEK Peroxide Catalyst for some DIY hobby projects, mainly to fuse plastic sheets and small pieces together, and it’s worked really well. The durability of the bond it creates is better than I expected. Once it cures, the pieces stay tight and clean. The functionality is exactly what I needed. It reacts fast and gives a strong hold, especially when paired with a syringe-style applicator, which makes the ease of use even better. Just make sure to apply slowly and precisely. For the price, the value for money is great. A little goes a long way, and the results are consistent. One thing to note is to use it in a well-ventilated space, since it’s strong stuff and you don’t want to breathe it in. Overall, it’s a reliable catalyst that performs the way it should and is perfect for plastic-related DIY work.

### ⭐⭐⭐⭐⭐ Wvercoat compatibility
*by B***I on March 7, 2026*

Great product. Works well with Wvercoat have gh strength fiberglass epoxy.

### ⭐⭐⭐⭐⭐ polyester resin catalyst
*by W***D on July 6, 2026*

Good catalyst for fiberglass resin

## Frequently Bought Together

- Mek Peroxide Catalyst 4oz Clear
- Wax Additive - 4 oz Surfacing Agent for use with Gelcoat and Polyester resins
- MEK Peroxide Adjustable Volume Dispensing bottle 16oz. (500ml)

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*Product available on Desertcart Uruguay*
*Store origin: UY*
*Last updated: 2026-08-15*