---
product_id: 1934494
title: "Permatex 81878 Ultra Copper Maximum Temperature RTV Silicone Gasket Maker, 3 oz. Tube"
brand: "permatex"
price: "70 zł"
currency: PLN
in_stock: true
reviews_count: 8
category: "Permatex"
url: https://www.desertcart.pl/products/1934494-permatex-81878-ultra-copper-maximum-temperature-rtv-silicone-gasket-maker
store_origin: PL
region: Poland
---

# 8x Flexibility Max Temp 700°F 3x Oil Resistant Permatex 81878 Ultra Copper Maximum Temperature RTV Silicone Gasket Maker, 3 oz. Tube

**Brand:** permatex
**Price:** 70 zł
**Availability:** ✅ In Stock

## Summary

> 🔥 Seal the deal with ultra copper power!

## Quick Answers

- **What is this?** Permatex 81878 Ultra Copper Maximum Temperature RTV Silicone Gasket Maker, 3 oz. Tube by permatex
- **How much does it cost?** 70 zł with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.pl](https://www.desertcart.pl/products/1934494-permatex-81878-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 cut gaskets—adapts perfectly to vibrations and movement.
- • **Sensor-Safe & Low Odor:** Non-corrosive and safe for sensitive engine sensors—no compromise on performance or comfort.
- • **Superior Oil Resistance:** Three times more oil resistant than standard silicones—keeps your seals intact under pressure.
- • **Unmatched Heat Endurance:** Handles extreme temps from -75°F to 700°F intermittent—engineered for high-performance engines.
- • **Universal Fit for Critical Components:** Ideal for exhaust manifolds, valve covers, oil pans, and more—your go-to gasket maker for every job.

## Overview

Permatex 81878 Ultra Copper RTV Silicone Gasket Maker is a high-performance, sensor-safe sealant designed for extreme temperature ranges (-75°F to 700°F intermittent). It offers superior adhesion, is three times more oil resistant and eight times more flexible than conventional silicones, making it perfect for turbocharged and high-performance engines. This 3 oz tube is ideal for exhaust manifolds, valve covers, oil pans, and other critical automotive components.

## Description

Permatex Ultra Copper. For 4-cylinder, turbocharged or high-performance engines. The most advanced, high temperature RTV silicone gasket available. Sensor safe, low odor, noncorrosive. Superior adhesion. 3 times more oil resistant than conventional silicones; 8 times more flexible than cut gaskets. Temperature range -75 deg. F. to 700 deg. F. intermittent; resists auto and shop fluids and vibration. Suggested Applications : Exhaust manifolds/headers, valve covers, oil pans, timing covers, water pumps, thermostat housings. 3 oz tube. Carded.

Review: Worked for furnace ducts - Working well on some ducting coming into and off of my furnace
Review: quality is good - good 😊

## Features

- Most Advanced, High Temp Rtv Silicone Gasket Available.Fit Type: Universal
- 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

## Technical Specifications

| Specification | Value |
|---------------|-------|
| ASIN | B0002UEOPA |
| Best Sellers Rank | #1,810 in Automotive ( See Top 100 in Automotive ) #6 in Gasket Sealers |
| Brand | Permatex |
| Brand Name | Permatex |
| Color | Copper |
| Customer Reviews | 4.7 out of 5 stars 3,177 Reviews |
| Full Cure Time | 24 Hours |
| Global Trade Identification Number | 00686226818782 |
| Included Components | Permatex 81878 |
| Item Form | Paste |
| Item Type Name | Gasket |
| Item Weight | 85 Grams |
| Liquid Volume | 3000 Milliliters |
| Manufacturer | PERMTX-LOCKT |
| Material Type | Metal |
| Surface Recommendation | Pipe |
| UPC | 686226818782 |
| Unit Count | 3.0 Ounce |
| Warranty Description | Manufacturer |
| Water Resistance Level | Waterproof |

## Product Details

- **Brand:** Permatex
- **Color:** Copper
- **Full Cure Time:** 24 Hours
- **Item Weight:** 85 Grams
- **Liquid Volume:** 3000 Milliliters

## Images

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

## Questions & Answers

**Q: Can this be used on a valve cover gasket to get a better seal?**
A: Yes.  It is better than OEM gaskets in that it conforms to any warpage, dents, dings, & other incongruities, whereas OEM gaskets are designed for factory new, perfect valve covers without flaws.  Withstands 700 degrees.

**Q: Can I use this product to seal several non-moving parts of a wood burning stove instead of the standard gasketing material?**
A: This gasketting goop is absolutely incredible for sealing wood stove parts.  I’d certainly never use it on the fire box.  But it can and will hold to moving parts in high temperatures.  It lasts for several years on one application.

**Q: can I use this to seal radiator tubes to a heat exchanger in my gas furnace? Gaskets no longer available for it.**
A: Greetings! As I don't know this application, specifically, I can say that say that Ultra Copper is excellent for sealing liquid coolant surfaces in truck/auto repairs. Temperature, up to about 800*F and pressures exceeding 15 psi will remain sealed with this product. U.C. remains a pliant sealing silicone "glue", but it won't harden, as epoxy does. If you need a sealer that also hastens, look elsewhere. If this is for a flange or any flat, secured surface, you're good-to-go. NO acetic acid in this product, if that's a plus for you.

**Q: Can I spread this on outside of exhaust manifold leak like you would caulk something or does it have to go between parts?  F150 '04 V8**
A: It is too much pressure and heat to use any caulk or rtv. Even muffler cement doesn't work. You might have a lean fuel mixture to cause the problem in he first place. Exhaust bolts rust solid from heat erosion, use the right amount of points on the socket to get bolts out(6 sided bolt--6 sided socket) Copper metal exhaust gaskets work well. Mr. Gasket brand.

## Customer Reviews

### ⭐⭐⭐⭐⭐ Worked for furnace ducts
*by N***E on December 4, 2025*

Working well on some ducting coming into and off of my furnace

### ⭐⭐⭐⭐⭐ quality is good
*by J***K on January 20, 2026*

good 😊

### ⭐⭐⭐⭐⭐ The Only RTV for High-Heat Engine Jobs
*by M***N on October 11, 2025*

If you're working on anything high-heat, like an exhaust manifold or turbo application, this is the only gasket maker to use. The Ultra Copper RTV is a workhorse—it handles maximum temperatures without breaking down, shrinking, or leaking. It goes on smoothly, cures quickly, and forms a super durable, tight seal. I've used it on headers where standard RTV would just burn up, and this holds strong. It's the professional choice for reliability under extreme heat. Essential for engine work.

## Frequently Bought Together

- Permatex 81878 Ultra Copper Maximum Temperature RTV Silicone Gasket Maker, 3 oz. Tube
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*Product available on Desertcart Poland*
*Store origin: PL*
*Last updated: 2026-02-06*