Works with or without heat. The actual unit is about 21.75" wide X 20" high. It has a mounting rim around the 2 side and top for mounting.
The side rims are about 1" wide and top about 1/2". Side rim has 3 holes in each side to screw fast. The item "NEW-Great World Electric Fireplace Insert LED-Remote Controlled-4800 BTUs" is in sale since Friday, August 24, 2018. This item is in the category "Home & Garden\Home Improvement\Heating, Cooling & Air\Fireplaces & Stoves\Fireplaces".The seller is "montague" and is located in Estill Springs, Tennessee. This item can be shipped to United States.