We sell the Williams line of vent free blue flame gas heaters. Williams is a USA company that manufactures most of their product line in the USA. The vent free heaters are manufactured in China, as are all other brands, but by buying the Williams brand you are at least supporting one of the last USA companies that still manufactures most of their products in the USA
We sell three sizes - 10k btu, 20k btu and 30k btu. All have built-in thermostats that will turn the heater on and off to keep an even room temperature. All are dual-fuel, meaning they will operate on natural gas or propane, without conversion. There is a switch on the back that turn to the gas type you are using. Then there are two gas inlets on the bottom of the heater - one for propane (LP) and one for natural gas (NG).