The big buddy heater requires 4 Size D batteries or you can also plug it into the electrical outlet if you don't have batteries however the batteries are essential for lighting the big buddy heater during a power outage or when you don't have any electrical power.
The big buddy heater is a great heater and a great way to stay warm during a power outage if you have no other form of heat source.
I love my big buddy heater and use it during power outages and wouldn't be without one.