Reducing Tee, Slip x Slip x Slip PVC Schedule 40 1-1/4" x 1" x 1" (401-158)

This 1-1/4" x 1" x 1" Schedule 40 PVC Reducing Tee (Slip x Slip x Slip) provides a three-way solvent-cement junction that simultaneously steps the inline run diameter down from 1-1/4" to 1" and provides a full-size 1" branch outlet — combining the function of an inline reducer coupling and a standard full-size tee into a single compact all-socket fitting body. Constructed in white Schedule 40 PVC, it offers reliable performance in commercial plumbing, irrigation, and light industrial installations where a 1-1/4" mainline must transition to a 1" pipe run while simultaneously providing a 1" branch tap at the same fitting location, without the need for a separate reducer coupling upstream of a standard tee.

The 1-1/4" slip socket run inlet accepts 1-1/4" PVC pipe for a permanent solvent-cement bond from the upstream mainline, while the 1" slip socket run outlet accepts 1" PVC pipe for a permanent solvent-cement bond on the continuing downstream run — reducing the inline run from 1-1/4" to 1" across the fitting body. The 1" slip socket branch outlet accepts 1" PVC pipe perpendicular to the run for a permanent solvent-cement bond, providing a full-size 1" branch tap at the same location as the run reduction. This configuration is distinct from all standard equal-run 401 series reducing tees documented in this catalog session (where both run ends are the same size and only the branch steps down) — in the 401-158, the run itself is asymmetric, with the inlet and outlet at different diameters, making this the correct choice when both an inline run reduction and a same-location branch tap are required simultaneously. The alternative to this fitting would be a 1-1/4" x 1" reducer coupling followed by a full-size 1" tee — requiring two separate fittings, two cemented joints, and additional pipe section length at the same assembly point; the 401-158 consolidates both functions into a single compact body, reducing fitting count and minimizing the assembly footprint at the transition point.

Rated to approximately 370 psi at 73°F (governed by the 1-1/4" inlet end), this tee is suited for standard commercial and light industrial pressure service. Its PVC composition provides excellent resistance to corrosion, scale, chlorinated water, and a broad range of chemical exposures, making it a reliable long-term alternative to metal fittings in moisture-prone or chemically active environments. NSF/ANSI 61 listing confirms suitability for potable water contact.

Apply solvent cement to both the pipe end and fitting socket at each port per ASTM D2564 procedures, using a primer appropriate for the pipe and fitting schedule. Insert pipe fully into each socket and maintain a quarter-turn during assembly for even cement distribution. Note that the run inlet (1-1/4") and run outlet (1") are different sizes — confirm pipe diameters before cementing each joint to avoid assembling the fitting in the incorrect orientation. Allow adequate cure time before pressurizing the system, and derate pressure ratings for elevated temperatures per published derating curves.

Specifications:

Industries & Applications:

• Irrigation & Water Distribution — Transitions a 1-1/4" socket mainline to a continuing 1" socket distribution run while simultaneously tapping a full-size 1" socket branch at the same location in agricultural and municipal irrigation systems — eliminating a separate reducer coupling plus tee assembly and reducing fitting count at the run step-down and branch tap point within a single all-cemented body
• Commercial Plumbing — Provides simultaneous 1-1/4" to 1" inline run reduction and full-size 1" branch tap in commercial building water distribution systems where a 1-1/4" supply main transitions to a 1" sub-main while also supplying a full-size 1" branch connection to an equipment feed, fixture supply header, or service line at the same fitting location
• Industrial Process Piping — Combines an inline run reduction and a full-size branch tap in a single fitting at 1-1/4" to 1" process water distribution headers, chemical feed assemblies, and equipment feed manifolds in water treatment, chemical processing, and manufacturing facilities where minimizing fitting count at run step-down and branch tap locations is a design priority
• Chemical Handling — Provides a corrosion-resistant, all solvent-cement simultaneous run reduction and full-size branch tap in systems conveying acids, caustics, fertilizer solutions, and other fluids incompatible with metal fittings, particularly at distribution sub-header transition points where a 1-1/4" main steps down to 1" while supplying a full-size 1" branch in a single compact all-cemented body
• Water Treatment & Aquaculture — Used at inline run step-down locations where a 1-1/4" socket distribution main must simultaneously transition to a 1" continuing run and supply a full-size 1" socket branch with NSF/ANSI 61 compliance required throughout the all-cemented assembly
• HVAC & Mechanical Systems — Provides a simultaneous inline run reduction and full-size branch tap on cooling tower supply headers, chilled water distribution mains, and chemically treated water system piping assemblies where a 1-1/4" socket run transitions to 1" while also supplying a full-size 1" branch at the same fitting location within the Schedule 40 pressure class