Middle Atlantic 5737WH Steel Open Base Extension Box – White

Overview

The Middle Atlantic 5737WH is a white steel open base extension box designed for the 500 and 700 Series raceway systems. At 4.75 in × 4.75 in × 1 in deep, the 5737WH provides a low-profile base fitting that extends outlet capacity at raceway termination points — the right piece when a standard base depth isn't enough to accommodate conduit entries, device mounting, or wiring transitions without cutting into wall finish. TAA-compliant construction makes it a viable choice for government and federally funded installations where trade agreement sourcing requirements apply. Sourced factory-new via channel-direct supply.

Compatibility

Designed for use with Middle Atlantic 500 Series and 700 Series steel raceway systems, including open base configurations in the 5737 family. Pairs with matching 5737-series base and fitting components to extend box depth at transition points. Finish matches white-painted steel raceway components in the same series — confirm your installed raceway color before ordering if mixing with ivory or other neutral variants. Consult the raceway and cord covers category for compatible channel, cover, and fitting components.

Installation Notes

The 1 in depth adds minimal wall projection — confirm that the combined stack depth of your base plus this extension fits within the finished wall recess or surface mount profile you're working with. Steel construction; standard raceway installation tools apply. No special torque specifications noted in manufacturer documentation.