---
product_id: 348637061
title: "81878-12PK Ultra Copper Maximum Temperature RTV Silicone Gasket Maker, 3 oz. (Pack of 12)"
brand: "permatex"
price: "€ 327.48"
currency: EUR
in_stock: true
reviews_count: 6
category: "Permatex"
url: https://www.desertcart.hr/products/348637061-81878-12pk-ultra-copper-maximum-temperature-rtv-silicone-gasket-maker
store_origin: HR
region: Croatia
---

# Temp range -75°F to 700°F 8x flexibility vs cut gaskets 3x oil resistance vs standard silicones 81878-12PK Ultra Copper Maximum Temperature RTV Silicone Gasket Maker, 3 oz. (Pack of 12)

**Brand:** permatex
**Price:** € 327.48
**Availability:** ✅ In Stock

## Summary

> 🔥 Seal the deal with Permatex Ultra Copper – where extreme performance meets flawless precision!

## Quick Answers

- **What is this?** 81878-12PK Ultra Copper Maximum Temperature RTV Silicone Gasket Maker, 3 oz. (Pack of 12) by permatex
- **How much does it cost?** € 327.48 with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.hr](https://www.desertcart.hr/products/348637061-81878-12pk-ultra-copper-maximum-temperature-rtv-silicone-gasket-maker)

## Best For

- permatex enthusiasts

## Why This Product

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

## Key Features

- • **Flexibility That Lasts:** Eight times more flexible than traditional gaskets, ensuring a perfect, lasting seal even under vibration and movement.
- • **Sensor-Safe & Low Odor:** Formulated to protect sensitive engine sensors while maintaining a low-odor, non-corrosive profile for a cleaner workspace.
- • **Superior Oil Resistance:** Triple the oil resistance of conventional silicones keeps your seals intact under the harshest conditions.
- • **Unmatched Heat Endurance:** Handles extreme temps from freezing cold to blazing 700°F intermittent heat—perfect for high-performance engines.
- • **Versatile Application Power:** Ideal for exhaust manifolds, valve covers, oil pans, and more—trusted by OEMs and pros alike for maximum reliability.

## Overview

Permatex 81878-12PK Ultra Copper RTV Silicone Gasket Maker is a professional-grade, high-temperature silicone sealant designed for automotive applications. It offers exceptional oil resistance, superior flexibility, and sensor-safe properties, operating reliably between -75°F and 700°F intermittent. This 12-pack of 3 oz tubes is engineered for durability and precision sealing on exhaust manifolds, valve covers, and other critical engine components, making it a top choice for performance and OEM maintenance.

## Description

Permatex Ultra Copper Maximum Temperature RTV Silicone Gasket Maker is the most advanced, high temp RTV silicone gasket available. Three times more oil resistant than conventional silicones and eight times more flexible than cut gaskets, it is sensor-safe, low odor, and non-corrosive with superior adhesion. Highest operating temperatures for 4-cylinder, turbocharged or high-performance engines and OEM specified, with a temperature range of -75 degrees fahrenheit to 700 degrees fahrenheit intermittent. Also resists auto and shop fluids and vibration. These gasket makers offer significant performance advantages, excellent torque retention and hi-temp, sensor-safe properties. Extended warranties, engine sensors and new component materials such as aluminum, bi-metal alloys and high-tech plastics, have created the need for superior RTV silicone gasket makers in both OEM production and service applications. Permatex always has the right gasket maker for your application.

Review: Do NOT apply on your exhaust flanges - My heart is still pounding as I was rushing in all directions trying to get something to extinguish the fire with. I applied this RTV on the collector flange, downstream the headers, to arrest a leak and correct the AFR reading on the wideband. I saw some smoke, and I thought maybe it's the high temp paint on the header. Next I saw flames, and you know the rest. Beware, for your own safety!
Review: 説明書通りに使えばきちんと効果を発揮します。 そして剥がしやすい。

## Features

- Most advanced, high temp RTV silicone gasket available
- Three times more oil resistant than conventional silicones; eight times more flexible than cut gaskets
- Sensor-safe, low odor, and non-corrosive with superior adhesion
- Temperature range -75F to 700F intermittent
- Suggested Applications: Exhaust manifolds/headers, valve covers, oil pans, timing covers, water pumps, thermostat housings

## Technical Specifications

| Specification | Value |
|---------------|-------|
| ASIN | B001REZA1W |
| ASIN  | B001REZA1W |
| Best Sellers Rank | #7,685 in Automotive ( See Top 100 in Automotive ) #42 in Automotive Fillers, Adhesives & Sealants #3,428 in Oils & Fluids |
| Brand Name | Permatex |
| Color | Copper |
| Customer Reviews | 4.7 4.7 out of 5 stars (3,141) |
| Customer reviews | 4.7 4.7 out of 5 stars (3,141) |
| Date First Available  | 21 November 2013 |
| Global Trade Identification Number | 30686226818783 |
| Included Components | Tube of Gasket Maker |
| Is Discontinued By Manufacturer  | No |
| Item Form | Liquid |
| Item Weight | 1.31 kg |
| Item model number  | 81878-12PK |
| Liquid Volume | 3 Fluid Ounces |
| Manufacturer | Permatex |
| Manufacturer  | Permatex |
| Material Type | Silicone |
| Product Dimensions  | 22.61 x 21.34 x 10.92 cm; 1.31 kg |
| Surface Recommendation | Pipe |
| Unit Count | 12 Count |

## Product Details

- **Brand:** Permatex
- **Colour:** Copper
- **Item form:** Liquid
- **Item weight:** 2.88 Pounds
- **Liquid volume:** 3 Fluid Ounces

## Images

![81878-12PK Ultra Copper Maximum Temperature RTV Silicone Gasket Maker, 3 oz. (Pack of 12) - Image 1](https://m.media-amazon.com/images/I/81PxU8Ql4PL.jpg)

## Available Options

This product comes in different **Size** options.

## Customer Reviews

### ⭐⭐ Do NOT apply on your exhaust flanges
*by A***N on 3 March 2023*

My heart is still pounding as I was rushing in all directions trying to get something to extinguish the fire with. I applied this RTV on the collector flange, downstream the headers, to arrest a leak and correct the AFR reading on the wideband. I saw some smoke, and I thought maybe it's the high temp paint on the header. Next I saw flames, and you know the rest. Beware, for your own safety!

### ⭐⭐⭐⭐⭐ Review
*by G***O on 2 February 2026*

説明書通りに使えばきちんと効果を発揮します。 そして剥がしやすい。

### ⭐⭐⭐⭐⭐ Review
*by E***O on 5 February 2025*

Este sellador de silicona de alta temperatura ha funcionado de manera excelente en las uniones del escape de mi motocicleta. Su resistencia al calor extremo garantiza un sellado duradero sin deteriorarse con el tiempo. La aplicación es sencilla y la adherencia es muy buena, asegurando que no haya fugas ni vibraciones molestas en las conexiones. Además, su formulación a base de cobre proporciona una excelente conductividad térmica y estabilidad en condiciones exigentes. En general, un producto confiable y altamente recomendable para sellar uniones expuestas a altas temperaturas, como sistemas de escape y componentes de motor. ¡Gran desempeño!

## Frequently Bought Together

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*Product available on Desertcart Croatia*
*Store origin: HR*
*Last updated: 2026-05-24*