Looking for the best 5 cubic-inch electrical boxes? We’ve got you covered with top picks like the Steel City RS12 and Carlon B618R-UPC, offering a mix of strength, durability, and ease of installation for your small projects.
Choosing the right electrical box can make or break your project. The 5 cubic-inch size balances space and simplicity for small jobs.
Steel City RS12 shines with its galvanized steel strength. It fits one duplex receptacle perfectly. 1/2-inch depth keeps it sleek yet sturdy.
Carlon B618R-UPC and BH614R offer non-metallic durability for bigger needs. Their old-work design adapts to any wall. Bright blue color makes wiring a breeze.
List of Top 3 5 Cubic-Inch Electrical Boxes
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Steel City RS12 4″ Square Box Surface Cover, 5 Cubic Inches, 1/2″ Deep, Glavanized Steel, for Use with One Duplex Receptable |
This Steel City RS12 4″ Square Box Surface Cover is perfect for electricians and DIYers who need a strong, reliable cover for one duplex receptacle. It fits well in tight spaces with its 5 cubic inches capacity and 1/2 inch depth. Made from galvanized steel, it’s built to last and keep things safe. |
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Carlon B618R-UPC 4-1/4″ Round Box, Old Work, Cubic Inches: 18″, Non-Metallic |
This product is perfect for homeowners and electricians installing or replacing ceiling fixtures. Its non-metallic, phenolic material and 18 cubic inch capacity make it ideal for old work applications where durability and safety matter. |
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Carlon BH614R 3-1/2″ Round Box, Old Work, Cubic Inches: 14.5″ Non-Metallic- Pack of 5 |
This Carlon BH614R 3-1/2″ Round Box is perfect for DIYers and electricians who need a reliable, non-metallic solution for old work projects. The pack of 5 makes it ideal for small to medium jobs. |
Detailed Reviews
Discover the top 3 electrical boxes with 5 cubic inches of space, handpicked for durability and ease of use. Each product is expert-reviewed and customer-approved, ensuring quality and value. Find the perfect fit for your home improvement needs and upgrade your electrical setup with confidence.
1. Steel City RS12 4″ Square Box Surface Cover, 5 Cubic Inches, 1/2″ Deep, Glavanized Steel, for Use with One Duplex Receptable

The Steel City RS12 is a 4-inch square box surface cover made from galvanized steel. It’s durable and built to last.
This cover holds 5 cubic inches and is 1/2 inch deep. It fits one duplex receptacle perfectly.
Use it for flush receptacles in any space. It’s simple to install and works great.
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Perfect For:
This Steel City RS12 4″ Square Box Surface Cover is perfect for electricians and DIYers who need a strong, reliable cover for one duplex receptacle. It fits well in tight spaces with its 5 cubic inches capacity and 1/2 inch depth. Made from galvanized steel, it’s built to last and keep things safe.
Ready to Purchase?
2. Carlon B618R-UPC 4-1/4″ Round Box, Old Work, Cubic Inches: 18″, Non-Metallic

The Carlon B618R-UPC is a 4-1/4″ round box made from strong non-metallic phenolic material. It is designed for old work installations, perfect for ceiling fixtures. The box measures 2 3/4 inches deep and holds 18 cubic inches of space.
This box is easy to install and very durable. It fits well in walls without needing extra framing.
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Perfect For:
This product is perfect for homeowners and electricians installing or replacing ceiling fixtures. Its non-metallic, phenolic material and 18 cubic inch capacity make it ideal for old work applications where durability and safety matter.
Ready to Purchase?
3. Carlon BH614R 3-1/2″ Round Box, Old Work, Cubic Inches: 14.5″ Non-Metallic- Pack of 5

The Carlon BH614R is a 3-1/2″ Round Box made of non-metallic material. It works for old work, fitting into existing walls easily. This pack includes 5 boxes, giving you extras for bigger projects.
Each box holds 14.5 cubic inches, offering space for wires and connections. The blue color helps it stand out in walls for quick access. It’s built durable for home electrical needs.
Carlon makes this box, a trusted name in Home Improvement. The model BH614R ensures quality and reliability.
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Perfect For:
This Carlon BH614R 3-1/2″ Round Box is perfect for DIYers and electricians who need a reliable, non-metallic solution for old work projects. The pack of 5 makes it ideal for small to medium jobs.
Ready to Purchase?
Buying Guide
Choosing the right 5 cubic-inch electrical box is easy with the right guide. We’ll help you find the perfect fit for your project.
Factors to Consider When Buying:
- Material: Choose between galvanized steel for strength or non-metallic for durability and ease of installation.
- Size and Depth: Ensure the box fits your space and devices, like a duplex receptacle.
- Installation Type: Decide if you need old-work for existing walls or surface-mount for new setups.
- Color: A bright color like blue makes wiring easier and helps spot the box in walls.
- Capacity: Check if the box holds enough space for wires and connections.
- Brand Reliability: Pick trusted brands like Steel City or Carlon for quality and peace of mind.