DeWalt 12/3 Lighted CGM Extension Cord (100 ft)

A cold-morning test that told me a lot

I first put the DeWalt 12/3 cord to work on a single-digit morning, running a block heater and a small space heater out to a truck parked street-side. The amber LED at the plug told me I had power at the source, and the green LED at the receptacle confirmed the ground was intact. I didn’t have to guess whether a tripped breaker, a bad outlet, or a sketchy ground was to blame if something didn’t turn on—the indicators answered the question before I even plugged anything in. That simple clarity has turned out to be the theme with this cord: it’s built to make the basics—power and ground—obvious and reliable.

Build and materials

This is a 12-gauge, 3-conductor, 100-foot SJTW cord rated 15A/125V (1875W). The jacket is thermoplastic and cold-weather rated to -40°F. Each conductor is soft-drawn, annealed copper, made up of 65 strands of 30 AWG wire. In practice, that high strand count makes a difference; for a long 12/3, it’s surprisingly pliable, especially compared with bargain cords that feel like rebar in the cold.

The ends are molded with oversized strain reliefs that actually do something. I’ve abused the female end by dragging a portable compressor around by the cord—ill-advised, but realistic—and I’m not seeing the early separation that cheaper cords develop. The blades and pins are nickel-coated, which resists oxidation and light surface pitting. After a month of jobsite weather, the plug still inserts smoothly and shows none of the chalky tarnish I usually see on bare brass.

The overall package weighs in around 13 pounds. You notice that when you’re carrying it across a muddy site, but it’s the trade-off for 12-gauge copper over 100 feet.

The LEDs and what they actually tell you

• Amber LED at the plug: Power present at the source/receptacle. If this isn’t lit, the issue is upstream (breaker, outlet, generator).
• Green LED at the female end: Continuous ground monitoring. If it’s off, you’ve lost ground continuity somewhere along the way.

I’ve had the green LED save me time diagnosing a floating ground on a portable generator hookup. It’s not a replacement for a plug-in tester or proper meter work, but it’s a fast, always-on indicator that keeps you from plugging a double-insulated tool with a metal accessory into a suspect circuit.

One caveat: in full daylight the LEDs are visible but not bright. At dusk or indoors they’re easy to read. Outside at noon you’ll need to shade them with a hand.

Flexibility and handling in the cold

The -40°F rating isn’t just marketing. In the teens and low single digits, the jacket stayed supple enough to coil without fighting me, and it didn’t memorize kinks. It’s still an SJTW thermoplastic jacket, not a rubber SOOW, so it won’t be as forgiving around sharp edges or hot surfaces. But for general outdoor use—snow, rain, and the occasional puddle—it held up and wiped clean.

If you work around oils and solvents, know your environment. SJTW shrugs off most spills but won’t match the oil and abrasion resistance of a rubber SOOW. For garages and woodshops it’s fine; for a machine bay with constant oil mist, I’d consider rubber-jacketed cord instead.

Performance under load (and the voltage drop math)

Voltage drop is where gauge and length matter. At 100 feet of 12 AWG, total round-trip conductor length is 200 feet. Copper’s resistance at 12 AWG is about 1.588 ohms per 1000 feet. Do the math:

• Resistance: 1.588 Ω/1000 ft × 200 ft ≈ 0.318 Ω
• At a full 15A: V = I × R ≈ 15 × 0.318 ≈ 4.8 V
• On a 120–125V circuit, that’s roughly 3.8–4% drop.

In practice, that means:
- 10–12A loads (miter saw, shop vac) run without complaint.
- A true 15A circular saw or portable table saw still runs, but startup inrush is where you feel it. Keep the cord fully uncoiled, use a dedicated 20A receptacle where possible, and avoid daisy-chaining.
- Resistive heaters are fine up to the rating, but again, uncoil the cord to keep heat buildup down.

I ran a 15A compressor and a contractor saw across this cord for a day of trim work. The saw’s startup was a hair softer than on a 25-foot lead, but cut speed and torque were normal. If you regularly push 15A tools at 100 feet, a 10/3 cord is the better (heavier) choice. For mixed loads up to 15A, this 12/3 is the right balance of performance and manageability.

Safety notes

• UL listed and cUL approved: baseline compliance is in place.
• Continuous ground monitoring: useful, especially with generators or older infrastructure.
• No built-in GFCI: use a GFCI-protected outlet or inline device when around water, outdoors, or with corded tools on metal frames.
• California Proposition 65: the cord contains materials that can expose you to lead. Standard for many PVC-jacketed cords, but worth noting for shops with strict policies.

As always, unspool fully under heavy loads. Coiled cords act like a heater.

Durability and wear

After being dragged across concrete, gravel, and salty slush, the jacket shows typical scuffing but no nicks. The molded ends haven’t loosened, and the plug blades show minimal marking—likely helped by the nickel coating. The female end grips well: snug without needing two hands to disconnect. There’s no locking feature or triple-tap; it’s a single outlet, which I prefer for full 15A loads.

I’d expect years of service out of this cord with basic care—no tight kinks, avoid door pinches, and don’t let it cook on a running generator muffler.

Ergonomics and storage

At 100 feet, any 12/3 is substantial. This one coils cleanly with an over-under technique and lays flat without the corkscrew twist cheaper cords develop. There’s no included reel or wrap strap, so plan on your own cord organizer. The jacket wipes down easily, and the bright yellow is easy to spot in snow or sawdust.

Who it’s for

• Jobsite users who need a reliable 100-foot reach for 120V tools up to 15A.
• Cold-weather users who value a jacket that stays flexible and LEDs that simplify troubleshooting in the dark.
• Generator users who want quick confirmation of power and ground.

If you’re a stationary shop user and rarely exceed 25–50 feet, you can drop down in length or gauge. If you routinely run high-amperage tools at triple-digit distances, consider stepping up to 10/3.

What I’d change

• LED brightness in daylight could be higher. They’re functional but subtle outdoors.
• A factory option with a triple-tap or locking connector would broaden utility.
• An SOOW rubber version would better serve oil-heavy environments, though it would add cost and weight.

None of these are deal-breakers; they’re more about tailoring for specific users.

Value

This sits in the premium category for a 12/3, and it feels like it. The combination of cold-weather flexibility, nickel-coated contacts, robust strain reliefs, and the dual indicator LEDs isn’t window dressing—it solves real problems. The lifetime limited warranty adds confidence, though like most warranties it doesn’t cover abuse.

If you only need an occasional cord for light yard tools, a cheaper 14/3 will do. If uptime and quick diagnostics matter, this is money well spent.

Recommendation

I recommend the DeWalt 12/3 cord for anyone who needs a dependable 100-foot extension in real jobsite or cold-weather conditions. It carries full 15A loads responsibly over long runs, stays flexible in the cold, and the power/ground indicators remove guesswork when you’re troubleshooting in the field. It’s heavier and pricier than bargain cords, and it lacks a built-in GFCI or multi-outlet end, but its build quality and clarity-in-use easily justify the choice for contractors, serious DIYers, and anyone relying on long runs in tough conditions.