Concentric hub x hub reducer coupling for transitioning between 3" and 4" PVC DWV pipe in a single fitting. Schedule 40 wall thickness and solvent-welded sockets give the joint the same strength as the surrounding pipe, so the size change does not become the weak point in a soil stack or building drain.

• Connection: 3" hub x 4" hub (solvent-weld socket both ends)
• Schedule 40 PVC, white
• Concentric (centerline-aligned) reduction
• Dual rated to ASTM D1785 (pressure) and ASTM D2665 (DWV)
• NSF listed
• Non-pressure DWV service; maximum operating temperature 140 deg F
• Made in the USA

Applications: Connect a 3" toilet-flange drop or branch into a 4" building drain or soil stack, transition between 3" and 4" main vent risers, or step a 3" horizontal branch into a 4" building sewer transition.

Installation tip: In a vertical orientation the concentric profile is fine. On a horizontal drain run, code (IPC/UPC) requires an eccentric (flat-top) reducer to keep solids moving - this concentric reducer is acceptable on vents and on vertical drain segments but should be swapped for an offset / flat-top reducer if used in a horizontal sanitary drain. Cut square, deburr, dry-fit, primer (purple), medium-bodied PVC cement, push together with a quarter turn, hold ten seconds.

Note: Not for use with hot-water distribution, compressed air, or fuel gas. For above-ground sanitary drainage only.