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Model #7128

Starting At

$789.00 MSRP
Where To Buy

Introducing the GP3500iO Open Frame Inverter featuring PowerRush™ Technology.

The Generac GP3500iO open frame inverter featuring new, advanced PowerRush™ technology delivers over 50 percent more starting capacity for tools and other motor-driven equipment—so you can do more with less.* Both quieter and lighter, it’s the ideal portable solution for camping, powering your RV essentials or tools.

Over 50 percent more starting capacity with new, advanced PowerRush™ technology so you can do more with less*

50 percent quieter for noise sensitive environments

25 percent lighter, helping reduce fatigue while improving portability

Clean power for sensitive electronics with TruePower

One simple-to-use dial that integrates start/run/stop functions with PowerDial

*Increases electrical current upon demand; above rated output when starting electric motors.


The Power to
Live. Work. Play.

Portable generators are a welcome addition to many activities at home, at work, and away. In an emergency, portable generators can provide critical backup power. They make camping and tailgating more comfortable. And contractors appreciate the flexibility portable power brings to the jobsite.

GP Series Accessories

Maximize your investment and maintain your Generac portable generator with a variety of accessories.

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Rated 5 out of 5 by from I have tried another of small generators and I should of gotten this year's ago This is a very economical generator good power with excellent fuel usage. I uses for portable power when I am traveling for work. This is one of the quietest generators I have ever had and used in the portable line. I definitely recommend this generator if anybody is looking for a small compact generator that is very easy to move and very portable. This is a replacement generator for a much more expensive generator that if I'd known this generator was as good I would have bought this generator and not had spent the $2,000 on the other generator that I am still fighting for under warranty
Date published: 2021-06-01
Rated 5 out of 5 by from performance operates as all reviews said it would. Love that it is so quiet and starts so easy.
Date published: 2021-03-23
Rated 4 out of 5 by from Louder than expected Heat shield over the muffler rubs against the muffler and is loud and annoying. I'll probably take it off and see if I can bend it away so the metals don't touch each other. I bought the generator to camp with so I want to make it a little more quiet. Haven't gone yet. Just filled the oil and put gas in it to test. Ran a heater and skill saw with no issues.
Date published: 2021-03-12
Rated 3 out of 5 by from Good generator but.. This is a good little generator, but the only thing I have a problem with is that there is no fuel cut off valve. The off/run/choke switch just turns the generator off and does not run the generator out of fuel. I’m thinking as far as storage. I know the manual talks about fuel stabilizer, but I think a fuel cut off valve would be great. I have owned a few generators in the past and all had a fuel cut off valve to run the generator out of fuel when not in use. I have never had an issue with my other generators, but this is a concern for me.
Date published: 2021-02-27
Rated 5 out of 5 by from Quiet and smooth Like so many others, we are experiencing fairly frequent outages. Most are quite brief but recently we had one that lasted all day. If it hadn’t been warmer weather we might have had a problem. So.,.. we took the plunge and bought a generator. Since we live on a townhouse and don’t own it, I decided to buy something with enough capacity for the essentials. I also wanted to be able to run as cord to the neighbours to keep them in heat as weIl. It also had to be quiet and reliable. Portability was important. I found everything I wanted in this model. I’m presently making a storage box to keep it outside do I don’t have to carry it up from the basement although it’s doable. I would recommend this product. As a matter of fact, I recommended Generac to my mother and sister in law. They got a larger one since they had the space and wanted something to run more things in the house. Noise level also wasn’t as big a factor for them.
Date published: 2021-02-18
Rated 5 out of 5 by from Primarily Backup We grew tired of our what seemed like twice monthly power outages-can anyone say aging infrastructure. I researched several generators and one constant was a brand name with a good reliability rating and one that was not out of reach of our pocket book. I picked a Generac non wheeled generator that is semi portable to me(75 lbs is semi for me).It will sit on a cart in our outdoor shed-where I can run it with the doors open. I installed a Reliant Generator through the wall outlet kit that allows running the generator while all our windows and doors can stay shut(hidden Cords). 3 pulls of the recoil is all it took for initial starting out of the box-and ran very steady. Now we can run a portable heat/AC unit if needed along with our other refrigeration and freezer. I need something that was large enough to run a couple of appliances at the same time and this generator was of sufficient amperage and voltage. We are very happy with our choice and after testing out it kept up quite well. Quiet and sufficient power for our needs. We're happy.
Date published: 2021-02-02
Rated 3 out of 5 by from Good product I think its a great generator, however it was damaged upon delivery. The housing cage was bent and the panel also a little bent up. Normally I would have sent it back but needed it ASAP. Overall it runs great but was extremely disappointed with the damage upon delivery.
Date published: 2021-01-30
Rated 4 out of 5 by from Best overall but still lacks features After extensive research I chose this for my RV as a dry camp accessory. It is the best value in inverter generators, but lacks one major feature. No wheels or handles, and there are none available as aftermarket add ons. Very cumbersome to manage without them, since it is quite heavy. Otherwise it has everything I wanted, and is reasonable quiet.
Date published: 2021-01-26
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GP3500iO is rated 4.6 out of 5 by 18.
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