Fernco 1056-42 Flexible Pvc Dwv Coupling 4x2

Product Description

The FERNCO 1056-42 is a 4-inch by 2-inch flexible PVC coupling designed for drain, waste, and vent (DWV) piping systems. It bridges the gap between dissimilar pipe materials and reduces from a 4-inch pipe to a 2-inch pipe in a single fitting. The elastomeric PVC body compresses around the pipe ends for a watertight seal, while the included 300-series stainless-steel clamps resist rust and corrosion. The additional band slots built into the clamp design allow for enhanced flexibility during installation. Licensed plumbers and pipefitters install this fitting during new construction, remodels, and repair work where rigid couplings are impractical.

This coupling is suited for residential and light commercial DWV applications where a flexible, underground-rated connection is required. It accommodates cast-iron, plastic, copper, steel, and lead pipe materials, making it a practical solution for retrofit and repair jobs involving older pipe materials alongside modern plastic pipe. The reducer profile is common in stack, branch, and drain line connections where pipe sizes change between floors or fixture groups.

Key Features

• Reduces 4-inch pipe to 2-inch pipe in a single flexible coupling
• Elastomeric PVC body rated for underground installation
• 300-series stainless-steel clamps resist rust and corrosion
• Additional band slots on clamps provide enhanced installation flexibility
• Compatible with cast-iron, plastic, copper, steel, and lead pipe materials
• Sold in a case pack of 10 units

Compatibility

Designed to connect cast-iron, plastic, copper, steel, and lead DWV pipe in 4-inch to 2-inch reducer configurations. Suitable as an OEM-style replacement or new-installation fitting for residential and light commercial drain, waste, and vent systems.

Installation Notes

Installation is performed by a licensed plumber in accordance with the International Plumbing Code (IPC) and applicable local codes. Shut off water flow and relieve any pressure in the line before cutting into an existing drain or waste stack. Pipe ends should be clean, deburred, and free of sharp edges before sliding the coupling into position. Tighten stainless-steel clamp bands evenly to the manufacturer-specified torque range using a nut driver or clamp tool — do not overtighten, as this can deform the elastomeric sleeve.

Technical Specifications

• Inlet Size: 4 inches
• Outlet Size: 2 inches
• Body Material: Flexible PVC (elastomeric)
• Clamp Material: 300-series stainless steel
• Application: DWV (Drain, Waste, Vent)
• Underground Rated: Yes
• Case Pack: 10 units

Standard Information

• Brand: FERNCO
• Manufacturer Part Number: 1056-42