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Compare Generators Side-by-Side

Select up to 4 generators to compare specs, power output, noise levels, runtime and more. Your compare URL is shareable.

  • DuroStar DS4000S
  • Firman W03383
  • Model DS4000S
    Model DS4000S

    DuroStar 3,300W Gas Generator

    3300W
    Running
    69 dB
    Noise
    View details
  • Model W03383
    Model W03383

    Firman 3,300W Gas Generator

    3300W
    Running
    58 dB
    Noise
    View details
Quick charts
Each chart uses its own Y-axis scale (so numbers are comparable within a chart).
Running watts
W
Starting watts
W
Noise
dB
Runtime @50%
h
Running watts by fuel
Shows how output changes across gasoline/propane/natural gas (when available).
Generator Specifications Comparison
SpecificationDuroStar DS4000SFirman W03383
General
Product type
Generator
Generator
Fuel
Gasoline
Gasoline
InverterNoYes
Parallel capableNoYes
RV readyNoYes
Running watts
Winner: Winner: 3300 W
Winner: Winner: 3300 W
Starting watts
Winner: Winner: 4000 W
3650 W
Noise (lower limit)
69 dB
Winner: Winner: 58 dB
Weight
92 lbs
Winner: Winner: 91 lbs
Run time @50% load
Winner: Winner: 12 h
Not available—
Run time @25% load
26 h
9 h
Fuel tank
4 gal
1.8 gal
Fuel gaugeYesNo
Approx. dimensions (L × W × H)
23 x 18 x 17.5
23.2 x 17.8 x 17.9
Electrical
Voltage (AC)
120
120
Voltage (DC)
Not available—
12
GFCI outletsNoNo
Covered outletsNoYes
Automatic Voltage RegulationYesYes
THD
Not available—
<3% %
Engine
Engine
DuroStar OHV 4-stroke
193 cc Firman Max-Pro Series OHV 4-stroke, cast iron sleeve
Alternator
Not available—
Not available—
Starting system
Recoil
Recoil, Electric, Remote
Warranty
Warranty
3 years
3 years
Power by fuel
GasolineNot available—Not available—
Running watts
3300 W
3300 W
Starting watts
4000 W
3650 W
Running amps (120V)
Not available—
Not available—
Running amps (240V)
Not available—
Not available—
Peak amps (120V)
Not available—
Not available—
Peak amps (240V)
Not available—
Not available—
Run time @50% load
12 h
Not available—
Run time @25% load
26 h
9 h
Other
Data center
Not available—
Not available—
Indicators
true
true
Compliance
CARB, EPA
CARB, EPA
Security
Not available—
Not available—
Spark arrestorYesYes
Neutral
Floating
Not available—
UPC
811640011840
840876133835
Core / High-priority specs
Running Watts (Gasoline)
3300
3300
Starting Watts (Gasoline)
4000
3650
Runtime @ 50% Load (Gasoline)
12
Not available—
Runtime @ 25% Load (Gasoline)
26
9
AC Outlet Types
1x Duplex 120V 20A (5-20R); 1x 120V 30A (L5-30R)
1x Duplex 120V 20A (5-20R)1x 120V 30A (TT-30R)
Electrical & power
Frequency
60
60
Engine & construction
Engine Type
OHV 4-stroke
OHV 4-stroke
Engine Displacement
208
193
Cylinder Sleeve
Not available—
cast iron sleeve
Engine Oil Type
10W-30
Not available—
Runtime & fuel system
Runtime @ 25% Load (Gasoline)
26
9
Runtime @ 50% Load (Gasoline)
12
Not available—
Safety & compliance
Overload Protection System
Low oil and overload protection
Not available—
Low Oil ProtectionYesYes
Included equipment
Included Accessories
Funnel and tool kit
Oil, funnel, tool kit, key fob, battery charger, battery charging cables, and battery
Additional specs
Summary
The DuroStar DS4000S is a 3,300-watt gasoline generator built around a DuroStar OHV 4-stroke engine that delivers 4,000 peak watts for startup surges. This wattage range powers essential household appliances, power tools, and small job site equipment simultaneously. A single person can operate it because the recoil starting system requires only manual pull-cord engagement, though the 92-pound weight means transport over distance demands planning. The 4-gallon fuel tank runs 26 hours at 25 percent load or 12 hours at 50 percent load, making it suitable for extended outages or multi-day outdoor use without constant refueling. EPA and CARB compliance clears this unit for all 50 states.
The Firman W03383 is a 3300-watt inverter generator built around a 193cc OHV 4-stroke engine with a cast iron sleeve. At this wattage, it can run a refrigerator, microwave, and several lights simultaneously, or power essential household circuits during an outage. The inverter technology keeps total harmonic distortion below 3%, which protects laptops, smartphones, and other sensitive electronics from voltage spikes. This unit bridges the gap between lightweight portables and mid-range backup power, making it useful for both recreational trips and emergency home backup.
  • Most Powerful
    DuroStar DS4000S
    3300W running
  • Quietest
    Firman W03383
    58 dB
  • Longest Runtime
    DuroStar DS4000S
    12h at 50% load
Where to buy
Prices can change. We update these automatically.
DuroStar DS4000S
Store links
No links yet.
Firman W03383
Store links
No links yet.
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