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WEN

WEN RV-Ready 4000-Watt Open Frame Inverter Generator (GN400iM)

  • Based on 34 reviews
Condition: New
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Availability: In Stock.
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Arrives Sunday, Oct 18
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Style: 4000W, Inverter


Features

  • Generates clean power to safely operate sensitive electronics such as phones, tablets, TVs, and computers
  • Parallel-ready panel allows you to connect any 2 WEN inverter generators for increased wattage output
  • 212cc 4-stroke engine produces 4,000 surge watts and 3,500 rated watts
  • Lightweight body weighs 30% less than a standard 4000-watt generator
  • Includes two 120V NEMA 5-20R receptacles, two 5V USB ports, one 120V RV-ready TT-30R receptacle, and a two-year warranty

Description

Remember when you had clean and quiet portable power? The WEN® 4,000-watt inverter generator provides clean energy, free of voltage spikes and drops for safe use with laptops, phones, and other sensitive electronics. Designed to mirror a pure sine wave, this generator limits total harmonic distortion to under 0.3 percent at no load and under 1.2 percent at full load, making it safe to run sensitive electronics. Our ultra-efficient 1.85-gallon tank provides over seven hours of half-load run time. Maximize fuel economy by engaging the eco-mode switch. This allows the generator's engine to automatically adjust its fuel consumption as items are plugged into and unplugged from the panel, preventing the unnecessary usage of gasoline. Need more energy? Easily link up two generators using a WEN® Parallel Connection Kit (sold separately) in order to share wattage amongst multiple units. Low- oil and low-fuel automatic shutdown combine with the built-in overload protection and indicator lights to safeguard both your generator and your electronics from damage. And because it's a WEN® product, your open frame inverter generator comes backed by a two-year warranty, a nationwide network of skilled service technicians, and a friendly customer help line, all to make sure you remember WEN®.

Brand: WEN


Wattage: 4000 watts


Fuel Type: Gasoline


Power Source: Fuel Powered


Recommended Uses For Product: Camping, Residential


Voltage: 120 volts_of_alternating_current


Output Wattage: 4000


Special Feature: Lightweight


Included Components: Two 120V NEMA 5-20R receptacles, two 5V USB ports, one 120V RV-ready TT-30R receptacle, and a two-year warranty See more


Color: Orange


Wattage: 4000 watts


Fuel Type: Gasoline


Power Source: Fuel Powered


Recommended Uses For Product: Camping, Residential


Voltage: 120 volts_of_alternating_current


Output Wattage: 4000


Additional Features: Lightweight


Engine Type: 4 Stroke


Ignition System Type: recoil start


Tank Volume: 1.9 imperial gallons


Engine Displacement: 212 cubic centimeters


Total Power Outlets: 5


Starting Wattage: 4000 watts


Running Wattage: 4000 watts


Frequency: 60 hertz


Runtime: 7 hours


Item Dimensions L x W x H: 19.8"L x 13.8"W x 18.9"H


Brand Name: WEN


Included Components: Two 120V NEMA 5-20R receptacles, two 5V USB ports, one 120V RV-ready TT-30R receptacle, and a two-year warranty


Model Name: WEN RV-Ready 4000-Watt Open Frame Inverter Generator


Model Number: GN400iM


Number of Packs: 1


Number of Items: 1


UPC: 044459140016


Unit Count: 1 Count


Manufacturer: WEN


Item Type Name: WEN RV-Ready 4000-Watt Open Frame Inverter Generator


Manufacturer Part Number: GN400iM


Warranty Description: Two-year warranty


Color: Orange


Material Type: Metal


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Sunday, Oct 18

This item is non-returnable:

Non-returnable. Transportation of this item is subject to hazardous materials regulation

View our full returns policy here.

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Leasing options through Acima may also be available during checkout.

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Similar Products

Top Amazon Reviews

    • Affordable and Reliable Power!!!
Style: 4000W, Inverter
I purchased this generator specifically for emergency situations and it's exceeded my expectations. My goal was to find something affordable yet powerful enough to run two electric heaters in the winter or a portable A/C unit in the summer—and still have juice left for essentials like a lamp, phone chargers, and our modem/router. This unit handles all of that with ease. It may not have the extra bells and whistles found in higher-end inverter models, but I didn’t need those. What I wanted was reliability and simplicity, and this generator delivers. It starts with one pull and hums along at a reasonable volume (around 50 decibels from 25 feet away), which is perfectly in line with similar units. One standout feature is the eco mode, which adjusts the engine speed based on the power demand—saving fuel and reducing noise when the load is light. I also really appreciate the open-frame design—it makes it super easy to drain the carburetor after use, a huge convenience. Unlike some models, this generator doesn't have a carbon monoxide shutdown sensor. Personally, I prefer it that way. I’m very aware of the safety rules when operating a generator and never run it indoors or in confined spaces. Without the auto-shutdown, I don’t have to worry about wind triggering unnecessary shut-offs. It is a bit heavier than I anticipated, so I picked up a folding hand truck and now it's fully mobile—problem solved. It comes with a standard two-year manufacturer warranty, and I opted for the extended protection plan, giving me four years of peace of mind. Overall, I’m extremely satisfied with this purchase. It gives me confidence that we'll have power in any situation. ... show more
Reviewed in the United States on July 21, 2025 by Secret Agent Shopper
    • Quality inverter generator...
Style: 4000W, Inverter
This is a quality made small inverter generator, I own several inverter generators and this is fast becoming my favorite. It's easy to move around, cranks on the first pull and the noise level is quieter than expected with an open frame inverter generator. Run time on a gallon of gas is around 7.5 hours at 800 watts, it recharges my Bluetti ac180 without any problems, has a clean sine wave and steady 120 volts. For the price and simplicity to operate it is a great deal, plus no CO detector to worry about, just don't operate in a place that you're going to be sleeping or an enclosed area. It was easy to install an hour meter and I would recommend the Wen magnetic oil dipstick. ... show more
Reviewed in the United States on August 16, 2025 by Amazon Customer
    • 4000-Watt open frame
Style: 4000W, Inverter
Works perfectly! I bought this specifically because it has no CO auto-shut-off. As a retired "old-skool" mechanic I'm fully aware of the dangers of carbon-monoxide. I needed a generator that I could use to power either my 8 gallon air compressor or a 110V well pump out at the old farmstead. Of course it's always best to buy more watts than you ever expect needing. I finally got around to putting it to the test today and it can perform the intended tasks easily even in Eco-mode! It's small enough and light enough that I can even put it in the trunk of my car. If moving it a longer distance I can do so with my pneumatic tired two wheel cart. One thing I'd have preferred is a 12 volt outlet rather than the two USB ports but that's not a big deal. Mostly I like the simplicity of the open frame design. I've worked on a few of the fully encased models and find them frustrating! Like I prefer draining the gas out of the carb rather than closing the shut-off and letting the engine starve until it dies. Trust me, that stuttering and surging is NOT good for either the engine or the generator! With this open frame design it's easily done - no muss, no fuss! I'm so impressed with the general build quality that I'll look at more Wen products in the future! ... show more
Reviewed in the United States on February 3, 2025 by JW Wimpy
    • Quiet enough for weekend use
Style: 4000W, Inverter
I bought this generator for my home office so i can keep working when our old neighborhood loses power. The size is good for my little shed office and it fits fine next to my storage cabinet. It starts fast and runs my computer, router, and a small space heater without tripping anything. During a recent storm i had it running for about six hours straight while I finished payroll and a Zoom call. That part made me really glad I got it. My only complaint is the noise. It is quieter than the big construction ones but still louder than I hoped, so I have to wear earbuds if I’m on calls. ... show more
Reviewed in the United States on August 1, 2026 by Jessica Patrick
    • Decent for tailgates, loud for dorms
Style: 4000W, Inverter
I grabbed this for dorm power backup because our building loses power a lot during storms and i have a mini fridge, laptop, and a bunch of charging stuff. It does start up fine and runs my fridge and a fan at the same time, but it’s way louder than i expected for an “inverter” style. First night we tried it during a blackout and my roommate and i had to shout over it to talk. It also feels heavier than the listing made it seem, so dragging it from my car up the side of the dorm was a pain. It works, just not super dorm friendly. ... show more
Reviewed in the United States on September 23, 2026 by John Weeks
    • nice and reliable
Style: 4000W, Inverter
ran it for 4 days straight on a power outage runs nearly all day on a full tank. way less fuel use vs a larger generator and has enough to power anything. ran my lights tv and 2 fridges. paid for itself just from not having all my food go bad.
Reviewed in the United States on October 12, 2025 by Randy S.
    • Handy little generator for our RV
Style: 4000W, Inverter
I got this WEN generator for our family camper after the last trip where the kids complained about “boring” nights with no power. I pull it out on weekends, start it up while my husband sets up the awning, and we can run the AC and charge tablets without it being crazy loud. i like that it’s RV-ready so i just plug in and don’t have to hunt for adapters 😂. One evening it kept the slow cooker and a little outdoor string light going during a sudden outage at home, and the kids thought it was “camp night” instead of freaking out, which made me really glad we bought tgis thing 🙂 ... show more
Reviewed in the United States on September 24, 2026 by RES
    • Frustrating start with this generator
Style: 4000W, Inverter
I bought this for my home office so i could keep working when the power cuts out. The box looked fine but the air filter box and cover were already cracked when I opened it. Not a great first impression. I set it up anyway, followed the instructions step by step, added oil and gas, and it would start, run for a few seconds, then die. every single time. Now I’ve got a brand new generator that I have to haul to a repair shop before it’s ever been useful. For what I paid, that’s annoying. The size and features are exactly what I wanted for my desk setup and Wi‑Fi, but right now it’s just sitting in the garage like a very expensive doorstop. ... show more
Reviewed in the United States on September 24, 2026 by Edith M Viramontez

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