No-Hub Coupling

A no-hub coupling (also called a shielded coupling or band coupling) is a mechanical connector made of a neoprene rubber sleeve compressed between two stainless-steel bands that tighten with hose clamps or bolts. It bridges cast iron, PVC, ABS, or copper pipe ends that have no threaded hubs, making quick connections in tight spaces or when cutting existing lines.

The rubber core compresses around both pipes while the steel bands grip them axially, creating a watertight seal. No threads, no solvent cement, no flux—just cut your pipe square, insert both ends into the coupling, and tighten the clamps. For cast iron to PVC transitions or mid-run repairs, it's faster and more forgiving than threading or coupling with hubs. Size and flex rating vary; check the coupling against your pipe OD and application pressure.

Code-approved for most drainage, waste, and vent work, and sometimes for water lines depending on jurisdiction and coupling rating. The rubber degrades over time (15-30 years typically), so inspect during service calls. Never use a no-hub on undersized or out-of-round pipe, and always ensure both pipes are fully seated in the rubber core before tightening bands.