Southwire 12 Ga 2-Conductor NM-B 400 ft Cable - Reliable Indoor Wiring

Our review of the Southwire 12 Ga / 2 Conductor NM-B cable finds it well suited for residential and light commercial branch circuits where above-ground, dry-location wiring is required. The biggest reason to buy is its combination of a flame-retardant, crush-resistant PVC jacket and UL listing, which together make it a safe, durable choice for indoor projects like remodels or new branch circuit runs. Installers who need cable that pulls easily and holds up during handling will appreciate this option for standard 20 amp circuits up to 600 V.

Key Features

• Type NM-B construction: Designed specifically for residential and commercial branch circuits to meet common wiring needs indoors.
• 600 V rating: Approved for service to 600 volts, providing a robust safety margin for typical branch-circuit applications.
• PVC jacket and insulation: Flame-retardant PVC jacket and PVC insulated, nylon jacketed conductors offer durability and protection during installation.
• Built-in grounding: Includes a grounding conductor for code-compliant, safe branch-circuit wiring.
• UL listed: Underwriters Laboratories listing assures the cable meets accepted safety and performance standards.
• Crush-resistant design: Tough outer jacket helps the cable survive handling and pulls through cavities without damage.

Who It's For

This cable is aimed at electricians, contractors, and experienced DIYers performing indoor wiring for homes, apartments, or light commercial spaces who need a dependable 12 gauge, 2-conductor run for 20 amp circuits. It works well for standard circuits such as receptacles, lighting circuits, and bathroom remodels where wires must remain above ground in dry locations.

It is not intended for underground use, direct burial, or wet locations, so installers who need outdoor-rated or conduit-exposed wiring should look for products rated for those environments. Also, projects requiring multi-conductor or armored cable types should consider alternatives.

Pros & Cons

Pros

• Well-made PVC jacket and insulation that make the cable easy to work with and resistant to crushing during pulls.
• UL listing and 600 V approval give confidence in safety and compliance for indoor branch circuits.
• Customers report good value for money and that the cable pulls easily through runs and conduits.

Cons

• Restricted to above-ground, dry locations only, so it cannot replace outdoor or wet-location rated cable.

Specifications

Brand	Southwire
Conductor size	12 Ga
Configuration	2 conductor with ground
Length	400 ft
Voltage rating	600 V
Temperature rating	90 Deg C
Listing	UL listed

Our Verdict

For indoor branch-circuit wiring where above-ground, dry-location cable is required, this Southwire 12 Ga NM-B cable is a practical, cost-conscious choice. Its flame-retardant PVC jacket, UL listing, and ease of installation make it especially good for remodels and routine electrical runs, delivering dependable value for residential and light commercial jobs.

Frequently Asked Questions

Can this cable be used outdoors?
No. It is intended for above-ground, dry locations only and is not rated for outdoor or wet use.

Is this cable suitable for 20 amp circuits?
Yes. The 12 gauge conductor is appropriate for 20 amp branch circuits and is rated to 600 V.

Does it include a ground conductor?
Yes. The product includes a grounding conductor and uses PVC insulated, nylon jacketed conductors.