4X3 CI CLOSET RINGS RED

A 4" x 3" cast iron closet ring (closet flange) is a heavy-duty plumbing fitting designed to connect a toilet to a drain pipe in DWV (drain, waste, and vent) systems. It features a 4-inch flange opening for the toilet connection and reduces to a 3-inch pipe outlet, which is standard for residential waste lines.

Key Features

• Material: Durable cast iron construction for long-term strength and reliability
• Size: 4" inlet × 3" outlet (reducing flange)
• Finish: Red coated (helps resist corrosion and identify fitting type)
• Design: Notched and slotted ring to secure closet bolts and allow alignment
• Standards: Typically meets plumbing standards such as ASTM and ANSI for DWV systems

Function

• Provides a secure mounting point for a toilet
• Connects the toilet outlet to the drain pipe below the floor
• Ensures a watertight seal when used with a wax ring
• Allows proper alignment and anchoring to the finished floor

Applications

• Residential and commercial bathroom installations
• Sewer, sanitary, and drainage systems
• Retrofit or replacement of existing cast iron flanges

Additional Notes

• The 4x3 configuration is common because toilets discharge effectively into a 3" line while maintaining a wider flange opening for fit and flow
• Cast iron versions are preferred in commercial, multi-family, or retrofit jobs where durability and fire rating matter