1. Introduction
This manual provides instructions for the proper installation and use of the RACO Hubbell-Raco 779 Square Mud Ring Cover. This product is designed to facilitate the mounting of two electrical devices within a 4-inch square electrical box, providing a 3/4-inch raised surface for flush installation with finished wall surfaces.

Image 1.1: The RACO Hubbell-Raco 779 Square Mud Ring Cover, a galvanized steel component designed for electrical installations.
2. Safety Information
Always follow local electrical codes and regulations. Ensure power is disconnected at the circuit breaker before beginning any electrical work. If you are unsure about any part of the installation process, consult a qualified electrician.
- This product is cULus Listed, indicating compliance with applicable safety standards.
- Wear appropriate personal protective equipment (PPE) during installation.
- Verify all connections are secure before restoring power.
3. Installation Instructions
The RACO 779 mud ring cover is designed for use with 4-inch square electrical boxes to mount two electrical devices.
- Prepare the Electrical Box: Ensure the 4-inch square electrical box is securely mounted and all necessary wiring is pulled through.
- Attach the Mud Ring Cover: Align the RACO 779 mud ring cover with the 4-inch square electrical box. The angled mounting slots are designed to compensate for up to 12 degrees of box misalignment, allowing for a level installation of devices. Secure the mud ring to the electrical box using appropriate screws.
- Install Electrical Devices: Once the mud ring is securely attached, connect your two electrical devices (e.g., outlets, switches) to the wiring according to their specific instructions and local codes. Mount the devices into the mud ring's openings.
- Finalize Installation: Secure the devices to the mud ring using their mounting screws. Install the decorative faceplate (not included) over the devices and mud ring for a finished appearance.

Image 3.1: A standard 4-inch square electrical box, ready for mud ring installation.

Image 3.2: Using a drill to fasten the mud ring cover to the electrical box.

Image 3.3: A screwdriver being used to tighten screws, securing the mud ring.

Image 3.4: An electrical outlet being inserted into the mud ring opening.

Image 3.5: A fully installed electrical outlet within the mud ring, prior to faceplate attachment.
4. Usage
The RACO 779 Square Mud Ring Cover serves as a mounting platform for two electrical devices, such as duplex receptacles or toggle switches. Its primary function is to bring the device flush with the finished wall surface, providing a clean and secure installation. Once installed, the mud ring itself does not require operational interaction; its purpose is fulfilled by supporting the electrical devices.
5. Maintenance
The RACO 779 Square Mud Ring Cover is constructed from durable galvanized steel and requires minimal maintenance. Periodically inspect the installation for any signs of corrosion or damage. If any issues are found, ensure power is disconnected before inspecting or replacing the component.
- Cleaning: If necessary, wipe the surface with a dry cloth to remove dust or debris. Avoid using abrasive cleaners that could damage the galvanized finish.
- Inspection: Check that all screws remain tight and that the mud ring is securely fastened to the electrical box and the devices.
6. Troubleshooting
Most issues related to mud ring covers stem from improper installation.
- Device Not Flush: Ensure the mud ring is correctly seated against the electrical box and that the electrical box itself is installed at the correct depth relative to the finished wall surface. The 3/4-inch raise of this mud ring is designed for specific wall depths.
- Misalignment: If the electrical box is slightly misaligned, utilize the angled mounting slots of the mud ring to adjust the device's position for a level installation. Loosen the mounting screws, adjust the mud ring, and re-tighten.
- Loose Devices: If devices feel loose after installation, ensure all mounting screws are tightened securely. Avoid over-tightening, which can strip threads.
7. Specifications
| Feature | Specification |
|---|---|
| Model Number | 779 |
| Brand | RACO |
| Manufacturer | Hubbell |
| Size | 2-Device, 4-inch Square |
| Raised Depth | 3/4 inch |
| Material | Galvanized Steel |
| Color | Metal |
| Item Weight (per 50-pack) | 6.8 Pounds |
| Number of Pieces | 50 |
| Certification | cULus Listed |
8. Warranty and Support
For warranty information or technical support regarding your RACO Hubbell-Raco 779 Square Mud Ring Cover, please contact the manufacturer directly. Refer to the official RACO website or product packaging for the most current contact details and warranty terms.

Image 8.1: RACO's commitment to quality and compliance.





