4 inch x 3 inch Flexible Banded Pipe Reducing Coupling Connects Cast Iron PVC Copper Steel or Lead Pipe

4" x 3" Flexible Banded Coupling – Engineered for Multi-Material Pipe Connections

The 4" x 3" flexible banded coupling is engineered to join pipes of dissimilar materials and sizes, including cast iron, plastic (PVC, ABS), copper, and steel. Featuring a stainless steel band clamp shield, this coupling provides added rigidity and alignment in buried or above-grade DWV systems. It is designed to meet ASTM and CSA standards for performance and durability in both residential and commercial drainage applications.

Product Advantages

• ✅ Shielded Design – The included 300-series stainless steel shear band provides added support for maintaining alignment under backfill loads and thermal movement
• ✅ Flexible Neoprene Sleeve – Resists common household chemicals and sewer gases, and allows slight deflection in the line
• ✅ Corrosion-Resistant Clamps – Worm gear clamps offer uniform compression and resist loosening under thermal cycling
• ✅ Code-Compliant – Conforms to ASTM C1173, CSA B602, and UPC/IAPMO-listed for use with non-pressure drainage systems
• ✅ Reduces Jobsite Downtime – Fast, tool-assisted installation eliminates the need for solvent welding, soldering, or threading

Technical Specifications

• Pipe Size: 4" x 3"
• Material: Elastomeric sleeve with stainless steel band and clamps
• Connection Type: Shielded flexible coupling with mechanical clamp fasteners
• Temperature Rating: Up to 140°F continuous, intermittent to 180°F
• Conformance: ASTM C1173, CSA B602, UPC listed

Typical Applications

This coupling is used in gravity-flow drain, waste, and vent (DWV) systems. Common installations include transitions between hubless cast iron and PVC, or adapting new plastic piping into existing galvanized or lead piping during retrofit and repair work. The coupling’s flexibility allows for slight misalignment while maintaining a gas- and watertight seal.

Installation Guidance

Installation requires only a torque wrench or 5/16" nut driver. Torque stainless steel clamps to manufacturer specifications (typically 60 in-lbs). Ensure both pipe ends are clean and cut square to achieve maximum seal integrity. No solvent cement or primer required.

Professional Insight

Flexible shielded couplings like this are an essential tool for service plumbers and remodelers working with aging infrastructure or mixed-material systems. Their ability to accommodate movement and prevent shear separation makes them indispensable in code-approved repair applications.

For secure transitions between pipe materials in DWV systems, the 4" x 3" flexible banded coupling offers dependable performance, code compliance, and fast installation. Choose this component to ensure long-term reliability in demanding field conditions.