---
product_id: 412545848
title: "Fernco Inc.P1056-43 4-Inch by 3-Inch Stock Coupling"
brand: "fernco"
price: "$51.29"
currency: USD
in_stock: false
reviews_count: 5
url: https://www.desertcart.us/products/412545848-fernco-inc-p1056-43-4-inch-by-3-inch-stock
store_origin: US
region: United States of America
---

# Compact 4.46 x 3.52 x 4.03 inch dimensions 4-inch to 3-inch flexible coupling No metal design for corrosion resistance Fernco Inc.P1056-43 4-Inch by 3-Inch Stock Coupling

**Brand:** fernco
**Price:** $51.29
**Availability:** ❌ Out of Stock

## Summary

> 🔩 Connect with confidence — the flexible fix your plumbing needs!

## Quick Answers

- **What is this?** Fernco Inc.P1056-43 4-Inch by 3-Inch Stock Coupling by fernco
- **How much does it cost?** $51.29 with free shipping
- **Is it available?** Currently out of stock
- **Where can I buy it?** [www.desertcart.us](https://www.desertcart.us/products/412545848-fernco-inc-p1056-43-4-inch-by-3-inch-stock)

## Best For

- fernco enthusiasts

## Why This Product

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

## Key Features

- • **Trusted by Pros:** 4.8-star rating from 180+ users confirms dependable performance
- • **Compact & Lightweight:** Under 1 lb and compact size for easy installation in tight spaces
- • **Seamless Pipe Connection:** Effortlessly joins 4" and 3" pipes with precision fit
- • **Corrosion-Free Durability:** All-plastic, no metal parts ensure long-lasting reliability
- • **Flexibility for Misalignment:** Adapts to slight pipe misalignments without leaks

## Overview

The Fernco 1056-43 is a high-quality, flexible plastic coupling designed to connect 4-inch and 3-inch pipes seamlessly. Its corrosion-resistant, no-metal construction ensures durability, while its compact size and flexibility accommodate slight misalignments, making it a trusted choice for professional and DIY plumbing solutions.

## Description

Fernco 1056-43 Coupling Flex 4X3 No Metal

Review: acople un drenaje de cuarto de lavado de 3" al drenaje principal del patio que es de 4" PVC - me resolvio el problema del desalineamiento en una instalacion donde tenia que insertar la descarga de un cuarto de lavado de 3" en un ramal de drenaje de 4" que corre hacia un registro en el patio de la casa. Quedo excelente muy buena alternativa de solucion. PVC ambos drenajes
Review: exactly as advertised - exactly as described and currently in use. no issues to install.

## Features

- Brand: Fernco
- Part Number: 1056-43
- Coupling Flex 4X3 No Metal
- Stock coupling
- Use to connect any two pipes
- 4.46-Inch x 3.52-Inch x 4.03-Inch

## Technical Specifications

| Specification | Value |
|---------------|-------|
| ASIN | B000BQWWLS |
| Brand | Fernco |
| Brand Name | Fernco |
| Colour | Black |
| Connector Type | Coupling |
| Customer Reviews | 4.8 out of 5 stars 184 Reviews |
| Exterior Finish | Black |
| Global Trade Identification Number | 00018578000117 |
| Included Components | Fernco 1056-43 Coupling Flex 4X3 No Metal |
| Item Dimensions | 14 x 14 x 10.7 Centimeters |
| Item Type Name | Fernco 1056-43 Coupling Flex 4X3 No Metal |
| Item Weight | 0.89 Pounds |
| Item dimensions L x W x H | 14 x 14 x 10.7 Centimeters |
| Manufacturer | Fernco Inc. |
| Manufacturer Part Number | 1056-43 |
| Material | Plastic, Stainless Steel |
| Material Type | Plastic, Stainless Steel |
| Model Number | 1056-43 |
| Number of Pieces | 1 |
| Size | 4 x 3 Inch |
| Thread Size | 4 inch |
| Thread Type | NPT |
| UPC | 018578000117 |
| Unit Count | 1.0 Count |

## Product Details

- **Brand:** Fernco
- **Colour:** Black
- **Connector Type:** Coupling
- **Exterior Finish:** Black
- **Global Trade Identification Number:** 00018578000117
- **Item Weight:** 404 g
- **Item dimensions L x W x H:** 23.5 x 23.5 x 15.2 Centimeters
- **Material:** Plastic, Stainless Steel
- **Number of Pieces:** 1
- **Size:** 4 x 3 Inch

## Images

![Fernco Inc.P1056-43 4-Inch by 3-Inch Stock Coupling - Image 1](https://m.media-amazon.com/images/I/61fRguyeu8L.jpg)
![Fernco Inc.P1056-43 4-Inch by 3-Inch Stock Coupling - Image 2](https://m.media-amazon.com/images/I/61Toq6o42LL.jpg)
![Fernco Inc.P1056-43 4-Inch by 3-Inch Stock Coupling - Image 3](https://m.media-amazon.com/images/I/61IfKAyhpwL.jpg)
![Fernco Inc.P1056-43 4-Inch by 3-Inch Stock Coupling - Image 4](https://m.media-amazon.com/images/I/71qmfHp69ZL.jpg)
![Fernco Inc.P1056-43 4-Inch by 3-Inch Stock Coupling - Image 5](https://m.media-amazon.com/images/I/71tBvrMRkZL.jpg)

## Questions & Answers

**Q: I have 3.25" pvc installed for a radon system.  Will this sleeve work or do I need to get a 4" x 4"?**
A: 3.52-Inch is the smaller side of this Fernco.  So it will fit your pipe.  However the other side of this Fernco is 4 ", and would work if your fitting it to a 4 inch pipe or other fixture.  I bought these Fernco 4x3 to join my Radon pipe to my radon inline fan. The fan was 4" on the inlet and the exhaust side.  Two Fernco couplings to complete one job.

**Q: Can someone please tell me what the outside dimensions on both sides are? I'm needing it for a different kind of project than pipe fitting.**
A: My coupling is already installed on the radon fan device, but I tried to take the O.D. measurements of the coupling for you; the 3" side measures 4.05" OD. The 4" side was more difficult to measure exactly with my calipers, but I measured it as 5" OD. I hope this helps you, but if your use requires dead accurate measurements, I would contact the manufacturer directly.

**Q: How flexible is the material? I have a 3.5 x 5.00 and am woondering if it will be flexible enough to stretch over the 5" end.**
A: I went into my garage and looked at one waiting for a project.  The large end measured 4 and a quarter inches inside diameter.  I loosened the band clamp on that end a lot and tried to stretch it.  It did flex some for me.  I think you may possibly be able to stretch it to 5 but not more.  The wall thickness of the rubber is about 3/8 inch so it won't stretch easily.  Using some Vaseline or other lube might help it go on.  I have not tried it on a 5 inch O.D. pipe.

**Q: will this fit over 4 inch pvc pipe**
A: It should fit the 4" PVC pipe, as that is what it is made for. I used it to connect to a 4" O.D. radon fan outlet to a 3" O.D. PVC pipe and it fit both fine. As another user commented, you can use Vaseline or a silicon lubricant on it if the fit is a little tight. Mine went on very easily with no lubricant and had to be tightened with the clamp.

## Customer Reviews

### ⭐⭐⭐⭐⭐ acople un drenaje de cuarto de lavado de 3" al drenaje principal del patio que es de 4" PVC
*by L***� on 22 July 2021*

me resolvio el problema del desalineamiento en una instalacion donde tenia que insertar la descarga de un cuarto de lavado de 3" en un ramal de drenaje de 4" que corre hacia un registro en el patio de la casa. Quedo excelente muy buena alternativa de solucion. PVC ambos drenajes

### ⭐⭐⭐⭐⭐ exactly as advertised
*by A***R on 8 May 2025*

exactly as described and currently in use. no issues to install.

### ⭐⭐⭐⭐⭐ Good quality buy it with confidence.
*by S***T on 13 January 2026*

Just as I expected, seems like good quality, used it to connect my radon mitigation fan to the pipe would buy again.

## Frequently Bought Together

- Fernco 1056-43 Coupling Flex 4X3 No Metal
- RadonAway 23029-1 RP140 Radon Mitigation Fan, 4",White
- XYF Air Easy Read Manometer | U-Tube Air Pressure Indicator (Blue)

---

## Why Shop on Desertcart?

- 🛒 **Trusted by 1.3+ Million Shoppers** — Serving international shoppers since 2016
- 🌍 **Shop Globally** — Access 737+ million products across 21 categories
- 💰 **No Hidden Fees** — All customs, duties, and taxes included in the price
- 🔄 **15-Day Free Returns** — Hassle-free returns (30 days for PRO members)
- 🔒 **Secure Payments** — Trusted payment options with buyer protection
- ⭐ **TrustPilot Rated 4.5/5** — Based on 8,000+ happy customer reviews

**Shop now:** [https://www.desertcart.us/products/412545848-fernco-inc-p1056-43-4-inch-by-3-inch-stock](https://www.desertcart.us/products/412545848-fernco-inc-p1056-43-4-inch-by-3-inch-stock)

---

*Product available on Desertcart United States of America*
*Store origin: US*
*Last updated: 2026-07-30*