---
product_id: 22127356
title: "John GuestAcetal Copolymer Tube Fitting, Union Straight Connector, 5/16\" Tube OD (Pack of 10)"
brand: "john guest"
price: "€ 45.14"
currency: EUR
in_stock: true
url: https://www.desertcart.fr/products/22127356-john-guestacetal-copolymer-tube-fitting-union-straight-connector-5-16
store_origin: FR
region: France
---

# Low moisture absorption Union connector 150 psi pressure John GuestAcetal Copolymer Tube Fitting, Union Straight Connector, 5/16" Tube OD (Pack of 10)

**Brand:** john guest
**Price:** € 45.14
**Availability:** ✅ In Stock

## Summary

> 🔧 Connect with Confidence!

## Quick Answers

- **What is this?** John GuestAcetal Copolymer Tube Fitting, Union Straight Connector, 5/16" Tube OD (Pack of 10) by john guest
- **How much does it cost?** € 45.14 with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.fr](https://www.desertcart.fr/products/22127356-john-guestacetal-copolymer-tube-fitting-union-straight-connector-5-16)

## Best For

- john guest enthusiasts

## Why This Product

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

## Key Features

- • **Durable Design:** Crafted from acetal copolymer plastic, ensuring high tensile and flexural strength for long-lasting performance.
- • **High Performance:** Engineered to withstand working pressures of up to 150 psi, making it ideal for demanding applications.
- • **Quality Assurance:** Meets NSF/ANSI standards 14, 51, and 61, guaranteeing reliability and safety in every connection.
- • **Seamless Connections:** Easily connect and disconnect inline pipes with our innovative union straight connector.
- • **Versatile Compatibility:** Accepts both nylon and polyurethane tube fittings for maximum flexibility in your projects.

## Overview

The John Guest Acetal Copolymer Tube Fitting is a pack of 10 union straight connectors designed for easy connection and disconnection of inline pipes. Made from durable acetal copolymer plastic, these fittings boast low moisture absorption and high tensile strength, with a working pressure capacity of up to 150 psi. They meet stringent NSF/ANSI standards for quality assurance, making them a reliable choice for various applications.

## Description

John GuestAcetal Copolymer Tube Fitting, Union Straight Connector, 5/16" Tube OD (Pack of 10)

## Features

- Union straight connector for connecting and disconnecting two inline pipes more easily than couplings
- Accepts nylon and polyurethane tube fittings
- Made of acetal copolymer plastic for low moisture absorption and high tensile and flexural strength
- Working pressure of up to 150 psi
- Meets NSF/ANSI standards 14, 51, and 61 for quality assurance

## Images

![John GuestAcetal Copolymer Tube Fitting, Union Straight Connector, 5/16" Tube OD (Pack of 10) - Image 1](https://m.media-amazon.com/images/I/61nwvyspBhL.jpg)
![John GuestAcetal Copolymer Tube Fitting, Union Straight Connector, 5/16" Tube OD (Pack of 10) - Image 2](https://m.media-amazon.com/images/I/71TJFa9d-nL.jpg)

## Available Options

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

## Questions & Answers

**Q: Is this a push to connect?**
A: Yes. It is a friction fit. I use the male inserts with barbed ends for tubing. To release, push in on the ring. Sometimes it takes a bit to get it to release. I have used John Guest fittings under pressure and vacuum. You can use rigid wall tubing to accomplish a good fit with same OD,

**Q: I used one to splice together my refrigerator water line tube after I had to remove a leaking section.  But, now I have no water flow.  What''s wrong?**
A: Suggest you remove and check to make sure nothing is blocking connector that would prevent water flow.  While you have the connector off, check to make sure water is flowing from the line ahead of where you placed connector.  Also, blow out the line below where you had connector installed.  Don't know if this will solve your problem but are the steps I would take to repair.

**Q: Is this compatiable with cpvc?**
A: These adapters work by a friction fit against an O-ring. I have used this fitting with Teflon tubing, Tygon with an insert to hold its shape, as well as other John Guest adapters. Assuming no chemical issues here, the question is whether your cpvc tubing is rigid and the correct outer diameter to get a good fit. I have found better, air-tight fits by trying to use just the tubing. The John Guest barbed inserts work with all tubing as long as you make sure to clamp the barb to keep the connection airtight.

**Q: what is the operating temperature?**
A: With a little effort, you can find this yourself.  From the product specs, you can learn that the fitting is qualified under NSF/ANSI standards 14, 51, and 61.  Searching on-line for these ANSI standards reveals in a PDF file the following:
© 2016 NSF 
NSF/ANSI 61 - 2016 17
4.2
  Definitions 
4.2.1   cold water application:
 A product application that is intended to result in continuous exposure to 
water of ambient temperature. Products are tested for an end-use temperature of 23 ± 2°C (73 ± 4°F).
4.2.2  commercial hot water application:
 A product application that is intended to result in continuous 
or intermittent exposure to water that has been raised from ambient temperature. Intermittent exposure is 
defined as any hot water contact that is not continuous. Products are tested for an end-use temperature 
of 82 ± 2°C (180 ± 4°F).
4.2.3 domestic hot water application: 
A product application that is intended to result in continuous or 
intermittent  exposure  to  water  that  has  been  raised  from  ambient  temperature.  Intermittent  exposure  is 
defined as any hot water contact that is not continuous. Products are tested for an end-use temperature 
of 60 ± 2°C (140 ± 4°F)

Thus, the fittings would be expected to qualify for at least those specified temperatures.  Of course, depending on what tubing you are using along with pressure in the lines, your mileage may vary.  

The Amazon description mentions that the fittings are good to 150 psi, but is silent on temperature.   You can further research this to see if you can find a section that specifies max pressure at a given temperature.   I cannot put the link in this message, I don't believe, but search Google on NSF/ANSI 61- 2016 Drinking Water System Components - Health Effects to locate the PDF file.  Then search it for pressure to see if that is listed.

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*Product available on Desertcart France*
*Store origin: FR*
*Last updated: 2026-01-28*