A two-way Fridge runs on 120, or propane.
A three-way adds 12 volt power to the equation.
But when they're running on the gas: they still use 12 volt power only for the purpose of temperature monitoring.
But the propane does the heavy-lifting.
Three-way Fridges use their batteries not only for temperature monitoring; but also for cooling.
Just like they'd use 120. :thumb
I've got a three-way, and it's a real trip to fire it up.
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