On a see-through fireplace the opening is a window as well as a firebox. You are not only looking at the flame, you are looking through it into the next room, so the height of the glass decides how much of that room you actually see.
A 16″ opening reads as a narrow letterbox: plenty of flame, very little sightline. Raising it to 24″ high opens the view considerably. The 30″ extra-high glass gives the largest uninterrupted opening between the two spaces of any Flare see-through model. The two rooms read as connected rather than divided by a wall with a slot in it, and the flame has the vertical room to be seen properly from both sides.
Most linear gas fireplaces offer a single narrow height. Flare builds see-through gas fireplaces in all three sizes, 16″ regular, 24″ high and 30″ extra-high, right across the 30 to 100 inch width range, so the opening can be sized to the wall and the view rather than the other way round.
