FlexPower® 4500ies Quiet Inverter Generator with Electric Start
4.8

FlexPower® 4500ies Quiet Inverter Generator with Electric Start

Sale price$849.00 Regular price$999.00
Generator model
Compare all models
Model Watts Weight Noise Start Fuel
4500ies Electric Start - Gas Only 4,500W peak 78 lbs 57 dB @ 23 ft Electric start Gas
4500ies Electric Start - Dual Fuel (Gas or LP ) 4,500W peak 78 lbs 57 dB @ 23 ft Electric start Gas + propane
3300ies Electric Start - Dual Fuel (Gas of LP) 3,300W peak — — Electric start Gas + propane
3300i Manual Recoil Start - Gas Only 3,300W peak 46 lbs 59 dB @ 23 ft Recoil start Gas
2200i Manual Recoil Start - Gas Only 2,200W peak 38.5 lbs 57 dB @ 23 ft Recoil start Gas
6500ies Electric Start - Gas Only 6,500W peak 111 lbs — Electric start Gas
6500ies Electric Start - Dual Fuel (Gas or LP) 6,500W peak 111 lbs — Electric start Gas + propane

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Free U.S. Shipping

Ships free inside the contiguous United States.

30-Day Returns

30-day money-back guarantee, no questions asked.

2-Year Warranty

Covers manufacturing defects, supported by our U.S.-based team.

After-Sale Service

US Based Support Team

Built for the Extreme. Trusted by Pros.

Skip the whole-home system.

A standby generator powers everything, all the time — and you pay for it. A portable inverter generator powers what matters during an outage, for about 5% of the cost.

WHOLE-HOME STANDBY$12,000–$20,000Installed. Permits, concrete pad, gas line, electrician — and weeks of lead time. Overkill if what you really want is the fridge cold and the heat on.
FLEXPOWER PORTABLE$519–$1,399Ready the day the box arrives. Add fuel, hit start, plug in. Quiet enough for a neighborhood, small enough for a garage shelf.
WHAT AN OUTAGE NEEDSUnder 4,500WFridge & freezer, sump pump, furnace fan, lights, Wi-Fi and phones. For most homes that's comfortably inside portable territory.

An inverter generator won't fry your fridge

Today's refrigerators, furnaces, and TVs all run on circuit boards — and circuit boards care about power quality. Conventional (non-inverter) generators put out rough, distorted power that overheats compressors and quietly cooks electronics. The damage often shows up weeks later, long after the outage. Inverter generators rebuild the power electronically into a clean sine wave — measured as total harmonic distortion (THD).

CONVENTIONAL GENERATOR 15–25% THD Voltage spikes and harmonic distortion. Hard on fridge compressors, furnace control boards, and anything with a power supply — laptops, TVs, CPAP machines.
FLEXPOWER INVERTER <3% THD FlexPower generators deliver a clean sine wave, with under 3% THD. That's the same THD as your local utility company. Safe for every circuit board in the house, from the fridge to your phone.

Every FlexPower model is an inverter generator — clean power is standard, not an upgrade. If a generator's price looks too good to be true, check its THD before trusting it with your refrigerator.

What do you actually
need to power?

Check what you'd want running in an outage. Running watts is the steady draw; starting watts is the 1–2 second surge when a motor kicks on. Size your generator for the surge, not the average.

Appliance Running Starting
Your Total
Running watts 0 W
Peak — with largest surge 0 W
2200i
3300i
4500ies
6500ies
YOUR MATCH Sizing rule: add up the running watts of everything you checked, then add the single largest startup surge on top. Motors (fridge, sump pump, furnace fan) rarely all start at the same instant.

Never owned a generator? Four things to know before the storm.

01 Run it 20 feet from the house, exhaust pointed away
Carbon monoxide is the one real danger. Never run a generator in a garage, carport, or near open windows — even 'just for a minute.' Every FlexPower has CO auto-shutoff as a backstop, but distance is the real protection.
02 Keep it dry — but never boxed in
Rain and generators don't mix. Use a purpose-built generator canopy or tent on grass or gravel so it stays dry and can still breathe. A sealed tote or running it inside 'to keep it dry' defeats the point above.
03 Run the cords, not the risk
Use a heavy-duty 12-gauge outdoor extension cord through a window or door gap and plug appliances into it directly. Never 'backfeed' power into a wall outlet — it's illegal and can electrocute the line worker fixing your street.
04 Hardwired equipment takes one electrician visit
Your furnace and well pump don't have plugs. A transfer switch or interlock kit — a few hundred dollars, installed once — lets the same portable generator power them safely through a single inlet on the outside of the house.
DUAL FUEL — AVAILABLE ON THE 4500IES & 6500IES

For emergencies, propane wins.

The #1 reason an emergency generator fails to start: gasoline that sat in the tank all year. Gas goes stale in months and leaves varnish that gums up the carburetor. Propane doesn't — the same 20 lb tank that runs your grill will start your generator on the first pull, years from now.

Gasoline sitting in your garage

  • ✕Goes stale in 3–6 months, even with stabilizer
  • ✕Gums up the carburetor — the classic "won't start" repair
  • ✕Cans need rotating, refreshing, and safe storage
  • ✕More engine maintenance over time

Propane sitting in your garage

  • ✓Never goes bad — no stabilizer, no rotation
  • ✓Burns clean. No carb gunk, cleaner oil, longer engine life
  • ✓Standard 20 lb grill tanks — swap one anywhere
  • ✓Stores safely outside, ready year-round

Dual-fuel FlexPower models run on either fuel: gasoline when you want maximum output, propane when the generator has been sitting since last season. Dual fuel adds $100–$220 to the price — cheap insurance for a machine you only start in emergencies.

Four sizes. One fits your home.

Every model: quiet inverter power, CO auto-shutoff, and free shipping in the contiguous U.S.

Flex Power® 2200i Silent Portable Inverter Generator- Gas Only

FlexPower® 2200i

2,200 starting W · 39 lbsPhones, lights, Wi-Fi — and the fridge in a pinch
$519.00$599.00
Flex Power® 3300i Silent Portable Inverter Generator- Gas Only

FlexPower® 3300i

3,300 starting W · 46 lbsThe basics: fridge, lights, Wi-Fi, chargers
$639.00$779.00
Most PopularDual Fuel
FlexPower® 4500ies Quiet Inverter Generator with Electric Start

FlexPower® 4500ies

4,500 starting W · electric startMost homes: fridge + sump pump or furnace
$849.00$999.00
Dual Fuel
FlexPower® 6500ies Quiet Inverter Generator

FlexPower® 6500ies

6,500 starting W · electric startEverything above with headroom — even an AC
$1,299.00

Outgrow it later? A $75–$95 parallel kit joins two FlexPower units into one connection — buy a second generator instead of replacing your first.

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