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Aquarium CO₂ Regulator Conversion Adapter, 5/8-18UNF Female to 3/8-24UNF Male Thread Brass Connector

Aquarium CO₂ Regulator Conversion Adapter, 5/8-18UNF Female to 3/8-24UNF Male Thread Brass Connector

Sale price  $19.80 USD Regular price  $21.00 USD
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Product Details

This brass CO₂ conversion adapter is designed to connect standard 95g or 74g CO₂ cartridges to equipment originally designed for 16g CO₂ cartridges or devices with a 3/8-24UNF female inlet thread. Equipped with a stainless steel piercing needle, it allows convenient CO₂ supply conversion for aquarium systems, beverage equipment, and other gas applications.

Product Specifications

Product Type: CO₂ Cartridge Conversion Adapter

Material: High-quality Brass

Thread Specifications:

  • Outlet Thread: 3/8-24UNF Male Thread
  • Adapter Body Thread: 5/8-18UNF Female Thread

Gas Inlet Structure:
Integrated stainless steel piercing needle for puncturing and connecting disposable CO₂ cartridges.

Compatible Gas Cartridges:

  • Standard 95g CO₂ cartridges
  • Standard 74g CO₂ cartridges

Application

Aquarium CO₂ Systems 

  • Converts 95g/74g CO₂ cartridges for use with aquarium CO₂ regulators.
  • Suitable for planted aquarium CO₂ injection systems requiring 3/8-24UNF connections.

Beverage & Draft Systems

  • Enables larger CO₂ cartridges to be connected to equipment originally designed for 16g CO₂ cartridges.
  • Suitable for beer dispensing systems and beverage carbonation equipment.

Other CO₂ Equipment

    • Compatible with devices featuring 3/8-24UNF female CO₂ inlet connections.
    • Provides a flexible solution for CO₂ cartridge compatibility conversion.

Note:
Uncoated brass may have minor surface marks or color variations. Natural oxidation and patina may develop over time due to the characteristics of brass material. These are normal and do not affect functionality.

About Piherk

At Piherk, we specialize in gas equipment solutions that combine functionality with durability. With our professional brand TYLEE®, we’re committed to delivering products that are practical, reliable, and crafted to solve real-world needs.

" Reliable Quality, Professional Solutions. "

When will I get my order?

We’ll ship your order as soon as possible.

Once shipped, you’ll receive a confirmation email with tracking details.

Orders ship within 3–5 business days after payment.

Delivery takes 7–20 business days depending on your location.

Guarantee

Change your mind? Return within 30 days.

Free Shipping

Enjoy free shipping when you spend $79 or more.

Q1-When should the sealing ring be replaced?

Replacement is recommended in the following cases:

  • When it shows visible wear, aging, or hardening;
  • If you notice air leakage during use;
  • As a general guideline, inspect it every 6–12 months depending on usage frequency.
Q2-Do I need tools to install the pressure regulator?

No tools are required. Our regulators use a soft-seal structure, so you can simply tighten them by hand. Using a wrench or other tools may over-compress the sealing ring and cause leakage.

Q3-How to choose the right thread for CO₂ cylinders?

Cylinder thread specifications vary by country, region, and application. Common CO₂ cylinder threads include:

  • CGA320 – Commonly used in USA and Canada for industrial CO₂ cylinders. In Australia, this thread is also commonly used for soda maker cylinders.
  • W21.8 – Common in Europe and the UK; sometimes referred to as BS341 No.6 / DIN477-6.
  • G5/8 – Common in China and other parts of Asia.
  • Tr21×4 – Often used in home soda makers.
  • JIS M22-18 – Common in Japan and Korea, similar in size to W21.8 but not directly interchangeable.

Important Notes:

  • Thread standards differ by application: industrial CO₂ cylinders vs. home soda machines.
  • W21.8 and JIS M22-18 threads are similar but cannot be used interchangeably; always verify the cylinder thread before use.
  • Always check your cylinder and device specifications to ensure compatibility.
Q4-How do I clean the regulator?

Wipe the exterior with a dry or slightly damp cloth. Do not immerse in water or use harsh chemicals.

Q5-Will there be any color difference between the product photos and the actual item?

All products are photographed from actual items without excessive rendering, aiming to show the true appearance and surface finish. Due to lighting and display variations, there may be slight color differences between the photos and the actual items. In addition, metal products may have minor scratches or imperfections. Please understand and take this into consideration before placing your order.

What Others Are Saying

Great First Impression!

Although I haven’t placed my first order yet, the website feels professional, and the product details are clearly written. I reached out to customer support with a few questions, and their response was quick and informative. Looking forward to trying it soon!

Jason Lee

Smooth Shopping Experience

From checkout to delivery, everything was seamless. The website is easy to navigate, and I loved the 30-day return policy—it gave me confidence to try something new!

James Miller

Well-Made and Exactly as Described

The quality of the product exceeded my expectations. It’s sturdy, professional, and looks even better in person. I appreciate that what you see is what you get.

Emily Carter

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