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.
- Firman P03503
- Sportsman GEN4000-SS
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).
| Specification | Firman P03503 | Sportsman GEN4000-SS |
|---|---|---|
| General | ||
| Product type | Generator | Generator |
| Fuel | Gasoline | Gasoline |
| Inverter | No | No |
| Parallel capable | No | No |
| RV ready | Yes | Yes |
| Running watts | Winner: Winner: 3550 W | 3500 W |
| Starting watts | Winner: Winner: 4450 W | 4000 W |
| Noise (lower limit) | Winner: Winner: 67 dB | 69 dB |
| Weight | 108.5 lbs | Winner: Winner: 91 lbs |
| Run time @50% load | Winner: Winner: 14 h | 10 h |
| Run time @25% load | Not available | Not available |
| Fuel tank | 5 gal | 3.9 gal |
| Fuel gauge | Yes | No |
| Approx. dimensions (L × W × H) | 24.8 x 21.7 x 21.7 | 23 x 19.5 x 17.5 |
| Electrical | ||
| Voltage (AC) | 120 | 120 |
| Voltage (DC) | Not available | 12 |
| GFCI outlets | No | No |
| Covered outlets | Yes | No |
| Automatic Voltage Regulation | Yes | Yes |
| THD | Not available | Not available |
| Engine | ||
| Engine | 208 cc OHV 4-stroke, cast iron sleeve. | 212 cc OHV 4-stroke |
| Alternator | Not available | Not available |
| Starting system | Recoil | Recoil |
| Warranty | ||
| Warranty | 3 years | 1 years |
| Power by fuel | ||
| Gasoline | Not available | Not available |
| Running watts | Not available | 3500 W |
| Starting watts | 4450 W | 4000 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 | 14 h | 10 h |
| Run time @25% load | Not available | Not available |
| Other | ||
| Data center | Not available | Not available |
| Indicators | true | false |
| Compliance | EPA, ANSI/PGMA G300-2023 | EPA |
| Security | Not available | Not available |
| Spark arrestor | Yes | Yes |
| Neutral | Floating | Not available |
| UPC | 840876135037 | 27077082470 |
| Core / High-priority specs | ||
| Running Watts (Gasoline) | Not available | 3500 |
| Starting Watts (Gasoline) | 4450 | 4000 |
| Runtime @ 50% Load (Gasoline) | 14 | 10 |
| AC Outlet Types | 1x Duplex 120V 20A (5-20R)1x 120V 30A (L5-30R)1x 120V 30A (TT-30R) | 2x Duplex 120V 20A (5-20R)1x 120V 30A (TT-30R) |
| Electrical & power | ||
| Frequency | 60 | 60 |
| Engine & construction | ||
| Engine Type | OHV 4-stroke, cast iron sleeve | OHV 4-stroke |
| Engine Displacement | 208 | 212 |
| Cylinder Sleeve | cast iron | Not available |
| Engine Oil Type | Not available | SAE10W-30 |
| Runtime & fuel system | ||
| Runtime @ 50% Load (Gasoline) | 14 | 10 |
| Safety & compliance | ||
| Overload Protection System | Low oil and overload protection | Low oil and overload protection |
| Low Oil Protection | Yes | Yes |
| Carbon Monoxide Monitoring | Yes | No |
| Included equipment | ||
| Starting Components | Not available | Recoil |
| Included Accessories | Oil, funnel, tool kit, cover, and wheel kit | Funnel, tool kit, and battery charging cables |
| Warranty & identification | ||
| Commercial Warranty | 3 | Not available |
| Additional specs | ||
| Summary | The Firman P03503 is a 3,550-watt gasoline generator built around a 208cc OHV 4-stroke engine with a cast iron sleeve. This wattage handles mid-range household loads: a refrigerator, microwave, and several outlets running simultaneously, or a modest RV power setup. The 5-gallon fuel tank delivers 14 hours of runtime at 50% load, meaning a full tank covers a typical overnight camping trip or a daytime power outage without refueling. The 4,450 starting watts give it enough surge capacity to turn on air conditioning compressors or well pumps, making it practical for both emergency backup and recreational use. | The Sportsman GEN4000-SS is a gasoline-powered generator offering 4000 surge watts and 3500 running watts, suitable for running RVs, household appliances, and power tools. |
- Most PowerfulFirman P035033550W running
- QuietestFirman P0350367 dB
- Longest RuntimeFirman P0350314h at 50% load
Where to buy
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Firman P03503
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Sportsman GEN4000-SS
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