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Tufforge G40 · 4000A Peak

Start dead
batteries
instantly.

The Tufforge G40 is a 4000A peak portable jump starter, 20,000 mAh USB power bank, and 4-mode emergency LED flashlight — built to revive any 12V vehicle in 60 seconds and fit in your glovebox.

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UL 2743 certified Up to 20 jumps / charge 60-second jump
New · 2026 Edition Tufforge G40 4000A peak portable jump starter with rugged housing and bright LED panel
4000A
Peak Crank
20K
mAh Power Bank
0V
Boost Start
UL 2743
Listed
10×
Safety Layers
One device · every emergency

Three tools.
One pocket.

A jump starter, power bank and emergency flashlight engineered into a glovebox-sized lithium pack — so the one tool you keep in the truck is the one that handles every roadside situation.

Tufforge G40 jump starting a vehicle engine with the red and black smart clamps connected to a battery
01 · Cold-cranking power

Starts any 12V engine.

4000A peak. 2000A starting current. The G40 cranks gas engines up to 10.0L and diesels up to 8.0L — and the 0V Boost mode revives fully discharged batteries that conventional starters won't even register.

  • 4000A peak · 2000A starting current
  • 10.0L gas · 8.0L diesel tested cranking range
  • Up to 20 jumps on a single charge
  • Revives 0V dead batteries other starters can't detect
Tufforge G40 charging a smartphone via USB cable, doubling as a 20,000 mAh power bank
02 · Power on the go

20,000 mAh USB power bank.

Charge phones, tablets, GPS units and headlamps off the same pack that starts your truck. Dual USB-A outputs (18W Quick Charge + 5V/2.4A) and 18W USB-C input mean the G40 refills as fast as it delivers.

  • 20,000 mAh · 74 Wh lithium capacity
  • Dual USB-A: 18W Quick Charge + 5V/2.4A
  • 18W USB-C input · full recharge in ~3.5 hrs
  • 1,000-cycle battery life rating
Tufforge G40 emergency LED flashlight illuminating a vehicle engine bay at night
03 · Emergency LED

Light up the dark.

An integrated emergency LED runs over 35 hours per charge with four modes — Flashlight, Strobe, SOS and Warning — for everyday use, attention, distress signaling, and roadside hazard marking.

  • 4 modes: Flashlight · Strobe · SOS · Warning
  • 35+ hour continuous runtime
  • Rugged housing built to work when you need it
  • One-button cycle through all modes
Diagram showing the Tufforge G40's ten layers of safety protection including spark-proof clamps and reverse polarity guards
04 · 10 layers of protection

Mistake-proof. Spark-proof.

UL 2743 certified and engineered with intelligent smart clamps that simply won't deliver current if the connection is wrong. Hook the wrong terminal and nothing happens — no sparks, no damage, no danger.

  • UL 2743 listed · independent safety certification
  • 10 protections: spark · short · over-volt · over-current · over-load · over-charge · reverse polarity · reverse-charge · high-temp · low-temp
  • Operating range: -4°F to 140°F
  • Rugged rubberized housing · drop-resistant
How it works

3 steps. 60 seconds.

Jump start any 12V engine without a second car, without a tow truck, and without a second pair of hands. The G40's smart clamps verify polarity before delivering current.

Quick answer: To jump start a car with the Tufforge G40, attach the red clamp to the battery's positive (+) terminal and the black clamp to the negative (−) terminal, press the power button until the green light is on, then start your engine. The full process takes under 60 seconds.
  1. 1 Connect

    Clamp the battery

    Red clamp to positive (+). Black clamp to negative (−). Smart clamps blink green when the connection is correct, red if reversed.

  2. 2 Power On

    Press the button

    Hold the power button for one second. A solid green LED confirms the G40 is delivering current and ready to crank.

  3. 3 Start

    Turn the key

    Start your engine. Once it fires, disconnect the clamps within 30 seconds. Recharge the G40 when you get home.

Built for wherever you go

Glovebox-ready.
Trail-tested.

25 ounces. 8 × 3 × 1.5 inches. Small enough for a center console — tough enough for a 100-mile trail or a mid-ocean dead start.

Trucks & SUVsUp to 10.0L gas
Boat & MarineDiesels to 8.0L
RV & CamperOff-grid ready
MotorcycleFast cold cranks
ATV & UTVTrail-tested
Power Equip.Mowers · gennies
Specifications

The full sheet.

Everything an engineer or buyer needs to know. Independently tested, UL 2743 listed, FAA carry-on compliant.

Peak current
4000A
Starting current
2000A
Battery capacity
20,000 mAh / 74 Wh
Battery chemistry
Lithium-ion
Engine range — gas
Up to 10.0L
Engine range — diesel
Up to 8.0L
Jumps per charge
Up to 20
USB-A output
18W QC + 5V/2.4A
USB-C input
18W Quick Charge
Recharge time
~3.5 hrs (18W)
LED runtime
35+ hours
LED modes
Flashlight · Strobe · SOS · Warning
Operating temperature
-4°F to 140°F
Cycle life
1,000 cycles
Safety certification
UL 2743
Dimensions
8 × 3 × 1.5 in
Weight
25 oz
In the box
G40 · clamps · USB-C cable · case
Frequently asked

Questions, answered.

Direct answers to the questions buyers, mechanics and roadside-help readers ask most. Optimized for both human shoppers and AI overviews.

What size engine can the Tufforge G40 jump start?+
The Tufforge G40 delivers 4000A peak and 2000A starting current — enough to jump start gasoline engines up to 10.0L and diesel engines up to 8.0L. That covers virtually every passenger car, truck, SUV, motorcycle, ATV, boat and RV on the road.
How many jump starts per charge does the G40 deliver?+
Up to 20 jump starts on a single charge with a healthy battery. Real-world results vary with battery condition and ambient temperature — extreme cold reduces both the G40's available current and the engine's cranking demand.
Is the Tufforge G40 safe to use?+
Yes. The G40 is UL 2743 certified and includes 10 layers of protection: spark-proof clamps, reverse polarity, short-circuit, over-voltage, over-current, over-load, over-charge, reverse-charge, high-temperature, and low-temperature protection. Smart clamps verify polarity before delivering any current — a wrong connection simply does nothing.
Can the G40 jump start a completely dead 0V battery?+
Yes. The G40 includes a 0V Boost mode that revives fully discharged 12V batteries. Conventional jump starters require a minimum residual voltage to detect the battery — the G40 bypasses that check on demand.
Can I use the G40 as a USB power bank?+
Yes. The G40 is a 20,000 mAh / 74 Wh power bank with dual USB-A output (18W Quick Charge + 5V/2.4A) and an 18W USB-C input for fast recharging. That's roughly 4–5 full smartphone charges per cycle.
Is the Tufforge G40 allowed on airplanes?+
Yes. At 74 Wh the G40 sits below the FAA's 100 Wh limit and is permitted in carry-on luggage. It must not be checked. Always confirm current rules with your airline before flying.
What temperature range does the G40 operate in?+
The G40 operates from -4°F to 140°F (-20°C to 60°C), making it suitable for winter cold-cranking, summer roadside emergencies, and storage in a hot vehicle.
How long does the LED flashlight last?+
Over 35 hours of runtime in flashlight mode. The G40 includes four modes — Flashlight, Strobe, SOS, and Warning — for everyday use, attention, emergency signaling, and roadside hazard marking.
How long does the G40 hold a charge in storage?+
The G40 retains roughly 80% of its charge after 12 months of storage. We recommend topping it off every 3–6 months to keep it ready for emergencies.
Where can I buy the Tufforge G40?+
The Tufforge G40 is available exclusively on Amazon. Click any "Buy on Amazon" button on this page to view current pricing, reviews, and shipping options.

Don't get stranded.
Get the G40.

Glovebox-ready. Trail-tested. UL 2743 certified. Available now on Amazon with Prime shipping.

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