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Standby generator accessories

Transfer switches, maintenance kits and must-have extras for the generators we review, all sold on Amazon. Pick your brand to filter.

Automatic transfer switches

Buying guide →

The switch that senses the outage and moves your home to generator power. Match the amperage to your panel.

  • Transfer switch
    Champion aXis automatic transfer switchOfficial Champion

    The Wi-Fi-enabled aXis ATS with priority load management — the brain that lets a 14kW unit run a bigger home. Fits: Champion 14kW. Confirm the amperage (100A/150A/200A) matches your panel.

  • Transfer switch
    Generac 200A service-entrance automatic transfer switchOfficial Generac

    The official 200A ATS Generac bundles with Guardian kits — buy it separately if your kit arrives without one or you're replacing a failed switch. Fits: Guardian 26kW, Guardian 24kW, Guardian 22kW, Guardian 18kW, Guardian 14kW.

  • Transfer switch
    Kohler RXT 200A automatic transfer switchOfficial Kohler

    Kohler's RXT switch with built-in load shedding, the match for RESCL/RCAL generators bought as bare units. Fits: Kohler 26RCAL, Kohler 20RESCL.

Maintenance kits & oil

Annual service kits with oil, filters and plugs — the cheap insurance that keeps the warranty valid.

  • Maintenance
    Champion standby generator maintenance kitOfficial Champion

    The annual service kit for the aXis line — cheap insurance for the 10-year warranty. Fits: Champion 14kW.

  • Maintenance
    Generac scheduled maintenance kit (oil, filter, plugs, air filter)Official Generac

    Everything for the annual oil-and-filter service in one box, matched to the G-Force engine. Fits: Guardian 26kW, Guardian 24kW, Guardian 22kW, Guardian 18kW, Guardian 14kW.

  • Maintenance
    Kohler home generator maintenance kitOfficial Kohler

    Oil, filter, spark plugs and air filter sized for the Command PRO V-twin. Fits: Kohler 26RCAL, Kohler 20RESCL.

  • Maintenance
    Full-synthetic 5W-30 small-engine oil (2-pack)Universal fit

    What most air-cooled standby engines drink. Keep a spare quart next to the generator.

Batteries & cold weather

Dead crank batteries are the #1 no-start cause. Maintainers and cold-weather kits fix that.

  • Battery
    Automatic battery trickle charger / maintainerUniversal fit

    Dead batteries are the #1 reason standby generators fail to start. A maintainer keeps the crank battery topped up year-round.

  • Battery
    Group 51R / U1R generator starting batteryUniversal fit

    The crank battery most standby units need (not included with the generator). Check your manual for the exact group size. Group size varies by model — confirm before ordering.

  • Cold weather
    Standby generator cold-weather kit (battery warmer + oil heater)Universal fit

    Keeps oil and battery warm so the unit cranks on the coldest nights. Champion's aXis doesn't need one; most others benefit below freezing.

Protection & extras

Whole-house surge protectors, weather covers and propane gauges.

  • Surge protection
    Whole-house surge protector (Type 1, panel-mount)Universal fit

    Generators switch power abruptly — a panel surge protector guards your electronics from the transition. Cheap peace of mind.

  • Cover
    Standby generator weather coverUniversal fit

    A breathable cover for units that sit unused for months. Remove it before the weekly exercise cycle. Measure your enclosure — air-cooled units vary in size.

  • Other
    Propane tank float gaugeUniversal fit

    Know your LP level at a glance. Running dry mid-outage is the most avoidable generator failure there is.

Compatibility checked October 2026. Confirm your exact model on the listing before buying.