What is the hole size of this?

Hello, this is a face trim only designed to fit the Majestic Jade fireplace. Click Here if you would like to view the fireplace itself and not just this accessory, there you will find all specifications needed to ensure this will fit your space including the viewing area which is 27 1/4"W x 15 1/4"H and the framing dimensions which is 37"W x 36 1/2"H x 17 3/4"D. If you have any further questions please feel free to give us a call! Thanks.