Southwire 63949202 8/3 NM-B Romex Copper Wire, 125 ft, Black

Product overview

Southwire 63949202 8/3 NM-B Romex copper wire in a durable black jacket is designed for everyday indoor wire runs. The SIMpull construction aims to make pulling through walls and spaces smoother, which can help your project stay on track. For professionals and DIY projects alike, this cable combines reliable grounding with a straightforward, non-metallic design.

Whether you’re updating a home or outfitting a small commercial space, this cable offers a familiar NM-B configuration with a ground conductor, a standard 125-foot length, and an 8-gauge three-conductor layout. The result is a practical solution that supports typical branch circuit layouts while keeping handling and installation in mind.

Why choose Southwire NM-B SIMpull

• Designed for residential and commercial branch circuits, delivering dependable performance in dry indoor spaces.
• SIMpull NM-B construction with a rugged outer jacket to help with pulling through conduits, stud bays, and tight channels.
• Approved for service to 600 volts, with a 90°C rating for approved indoor uses.
• 8 AWG, three-conductor configuration with a ground conductor supports standard circuit layouts and practical ampacity.
• 125-foot length reduces the need for frequent splices in common home install scenarios.

Key specifications at a glance

• Type NM-B non-metallic copper wire with ground
• Indoor use above ground, dry locations only
• 8 AWG, 3-conductor, 40A, 600V, 90°C
• Black jacket for easy identification and compatibility with standard indoor wiring jobs
• 125 feet per reel

Real-world use scenarios

Ideal for wiring living spaces, kitchens, basements, and small offices where a reliable NM-B cable is needed. The rugged, flexible jacket and the 125-foot length can help streamline runs through walls, attics, and crawl spaces while providing a familiar setup for standard circuits.

Installation notes and safety

• Use above-ground installations only, in dry locations, in accordance with local electrical codes.
• Keep the cable away from moisture and avoid exposing the conductor to physical damage.
• Follow proper securing and strain-relief practices at boxes and terminations.