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White PVC cleanout plug with male threaded end

Mueller Industries, Inc.

Mueller Industries, Inc. 1WKH9 4" MNPT PVC DWV Cleanout Trap

SKU CH-MHQQ-AXWC7 MPN 1WKH9

A 4-inch male NPT PVC cleanout plug for DWV systems, rated to 140 °F and built to ASTM D1784 cell class 12454

  • TypeDrain Components
  • ColorWhite
  • Schedule 40 PVC rated for 140 °F service
  • MNPT threads allow direct pipe connection
  • Meets ASTM D1784 cell class 12454
  • White finish suits visible DWV installations
  • Cleanout plug design simplifies drain access

4" MNPT PVC DWV Cleanout Plug

This 4-inch male NPT cleanout plug is made from Schedule 40 PVC and meets ASTM D1784 cell class 12454. It provides a white, solvent-weld compatible access point for drain, waste and vent systems. The fitting is rated for a maximum temperature of 140 degrees Fahrenheit. It is not rated for pressure applications.

Connection type and pressure rating

The single specification that determines fit is the 4-inch MNPT thread, which mates with a matching female adapter in DWV piping. Because the plug carries no pressure rating, it must only be used in non-pressurised gravity drainage.

Suitable for gravity DWV access.

This plug suits plumbers and contractors installing or maintaining residential and commercial DWV networks that require a 4-inch cleanout. Builders needing a pressure-rated test plug or a different pipe diameter should look at alternative fittings.

Highlights

  • Schedule 40 PVC rated for 140 °F service
  • MNPT threads allow direct pipe connection
  • Meets ASTM D1784 cell class 12454
  • White finish suits visible DWV installations
  • Cleanout plug design simplifies drain access

Specifications

TypeDrain Components
ColorWhite
BrandMueller Industries
Model1WKH9

Questions about this item

What does the 4-inch MNPT size mean when I thread this into my DWV line?

The 4-inch male NPT threads match standard Schedule 40 PVC drain fittings, so it screws directly into a female adapter or cleanout tee without reducers.

How does the Schedule 40 rating and ASTM D1784 cell class 12454 limit what this plug can handle?

Schedule 40 sets the wall thickness for gravity drainage only; the ASTM D1784 cell class 12454 PVC is rated to 140 °F and is not approved for pressure piping.

What clearance and tools do I need to install or remove this cleanout plug?

A 4-inch socket or large strap wrench engages the raised nut; allow enough swing radius for the handle and access to the threads for PTFE tape or pipe dope.

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