Eaton 373 Knockout Reducing Washer 2.5in Id 3.5in Od Steel

Product Description

The EATON 373 is a knockout reducing washer designed to close the gap between a conduit fitting and an oversized knockout opening in a steel electrical box. When a knockout is larger than the conduit or fitting being installed, this washer seats around the conduit and fills the unused space, maintaining a secure and code-compliant installation. Manufactured from steel for durability in standard electrical work environments, the 373 features a 2.5-inch inside diameter and a 3.5-inch outside diameter. Licensed electricians and electrical contractors install this component as part of conduit system assembly.

This reducing washer is suited for use with steel electrical boxes where IMC or rigid metal conduit enters through a knockout. It is a common component in commercial and industrial conduit installations where knockout sizes do not match the conduit trade size being used. The washer provides a flush, stable fit that supports proper grounding continuity and a clean box entry point.

Key Features

• Steel construction for strength and compatibility with standard conduit installation environments
• 2.5-inch inside diameter fits standard conduit fittings
• 3.5-inch outside diameter spans oversized knockout openings in steel boxes
• Compatible with IMC and rigid metal conduit systems
• Fills the gap between conduit fittings and larger knockouts to support secure, compliant entries

Compatibility

Designed for use with steel electrical boxes, IMC, and rigid metal conduits where a 2.5-inch inside diameter reducing washer is required to fit a 3.5-inch knockout opening.

Installation Notes

Licensed electricians install knockout reducing washers as part of conduit system assembly in accordance with NEC requirements. De-energize all circuits and verify lockout before working inside any electrical enclosure. Seat the washer flush against the box surface before tightening the conduit locknut to ensure proper contact and grounding continuity. Do not force or deform the washer, as distortion may compromise the fit and the integrity of the box entry.