Compare Generators Side-by-Side

Generator

Generator

4550 W

230 lbs

19 h

120/240

120V 60 Hz

457 cc OHV 4-stroke, cast iron sleeve

208 cc OHV 4-stroke, cast iron sleeve

Recoil, Electric

Recoil

5 years

3 years

12000 W

4550 W

19 h

9025 W

3300 W

3.5 h

CARB, EPA

EPA, ANSI/PGMA G300-2023

811640016227

840876136553

9500

3650

12000

4550

9

14

19

2x Duplex 120V 20A (5-20R); 1x 120V 30A (L5-30R); 1x 120/240V 30A (L14-30R); 1x 120/240V 50A (14-50R)

1x Duplex 120V 20A (5-20R); 1x 120V 30A (L5-30R); 1x 120V 30A (TT-30R)

60

60

OHV 4-stroke

208 cc OHV 4-stroke, cast iron sleeve

Cast iron sleeve

cast iron sleeve

19

3.5

Low oil and overload protection

Low oil and overload protection

Recoil, Electric

Oil, funnel, tool kit, propane hose, and wheel kit

5

3

The DuroMax XP12000HX is a 9,500-watt dual-fuel generator built for job sites, home backup, and RV use. Its 12,000-watt peak capacity handles the startup surge of air conditioners, compressors, and welders, while the 9,500-watt running output sustains multiple heavy tools or household circuits simultaneously. Gasoline delivers 19 hours of runtime at quarter load, making this unit suitable for extended outages or multi-day events without constant refueling. The dual-fuel design means users can switch between gasoline and propane depending on fuel availability and storage constraints. On propane at 25% load, runtime drops to 7 hours, trading endurance for cleaner emissions and longer shelf life. The 457 cc cast iron engine is built for durability on job sites where generators take abuse. This is a stationary workhorse, not a portable grab-and-go unit.

The Firman H03655 is a 3,650-watt dual-fuel generator built around a 208 cc OHV 4-stroke engine with a cast iron sleeve. Running on gasoline, it delivers 4,550 starting watts and 3,650 running watts. Switch to propane and output drops to 4,100 starting watts and 3,300 running watts. This power level runs a refrigerator, microwave, window air conditioner, or multiple power tools simultaneously. The dual-fuel flexibility means you can operate on whichever fuel is available, a practical advantage during extended outages or when propane storage is more convenient than gasoline. At 67 dB at quarter load, the H03655 operates quietly enough for residential neighborhoods without disturbing neighbors. The 5-gallon tank delivers 14 hours of runtime at 50 percent load on gasoline, translating to roughly one full day of moderate use before refueling. The RV-ready configuration and included wheel kit position this unit as a go-anywhere power source for camping, job sites, and home backup scenarios.