Brass Check Valve G1/2 Thread Anti-Backflow One-Way Valve

Keep your water lines flowing in the right direction with this Yellow Brass Check Valve featuring a G1/2 internal-to-external thread connection. Built from durable yellow copper (brass), this one-way valve is engineered to prevent backflow in household plumbing systems — ideal for bathrooms, toilets, water heaters, and general piping applications.

Its compact, reliable design makes installation straightforward with no specialist tools required. The threaded connection ensures a secure, leak-resistant fit, giving you confidence in your plumbing setup day after day.

Key Features

• Material: High-quality yellow copper (brass) — corrosion-resistant and built to last
• Thread Type: G1/2 internal (female) to G1/2 external (male) thread
• Function: One-way valve — prevents backflow and protects your plumbing
• Versatile Use: Suitable for bathrooms, toilets, water heaters, irrigation lines, and more
• Easy Installation: Standard thread size fits most residential plumbing connections
• Compact Design: Low-profile form factor fits in tight spaces

Specifications

• Thread Size: G1/2 (BSP)
• Connection: Internal thread inlet × External thread outlet
• Valve Type: Non-return / anti-backflow one-way check valve
• Body Material: Yellow copper (brass)
• Finish: Natural brass / yellow

What Is a Check Valve?

A check valve (also called a one-way or non-return valve) allows fluid to flow in one direction only. It automatically closes when flow reverses, protecting appliances, pipes, and water supplies from contamination or pressure-related backflow. For more information on plumbing safety and water quality, visit the U.S. Environmental Protection Agency — WaterSense.

Where to Use This Valve

• Bathroom and toilet water supply lines
• Water heater inlet connections
• Garden watering and irrigation systems
• General household plumbing upgrades

Frequently Asked Questions

Q: What thread size does this brass check valve use?

A: This check valve features a G1/2 (BSP) thread — G1/2 internal (female) on the inlet side and G1/2 external (male) on the outlet side. This is a very common size used in residential bathroom and toilet water supply connections, making it compatible with most standard household plumbing fittings.

Q: How does an anti-backflow check valve work?

A: A check valve contains an internal mechanism (typically a spring-loaded ball or disc) that allows water to flow freely in one direction. When flow stops or attempts to reverse, the mechanism closes automatically, blocking the backflow. This protects your plumbing system, appliances, and water supply from contamination or pressure surges.

Q: Is this valve suitable for both hot and cold water lines?

A: Yes. The brass (yellow copper) construction makes this check valve suitable for use on both hot and cold water supply lines found in standard residential plumbing applications, including bathrooms, toilets, and water heater connections.

Q: What tools do I need to install this check valve?

A: Installation typically requires only an adjustable wrench or pipe wrench to hand-tighten the threaded connections. Apply PTFE (thread seal) tape to the threads before fitting for a secure, leak-free connection. Always turn off your water supply before beginning any plumbing work.