What a peak-top vent is
A peak-top gable vent is a narrow vertical louver with a pointed top. The point echoes the roof peak without trying to fill the whole triangle the way a pitch-matched triangle vent does. The sides stay straight, so it still reads as a tall vent rather than as a miniature gable.
It is molded high-density polyurethane, factory-primed white, and ready for paint. It does not rot, and it cuts and fastens much like wood trim.
Where it looks right
Steep gables are the best setting. The point wants height around it. A low, wide gable makes a peak top look like a candle on a cake. Center it under the ridge, with the point aimed at the peak and clear of the rake boards.
It also works on a tall dormer face, where a circle would be wider than the wall allows. Keep it on the center line of that dormer.
Open or closed
open peak-top gable vents move air through a tall, narrow opening. closed peak-top gable vents keep the pointed outline for looks only. Because the opening is narrow, an open peak top is a modest vent. Do not expect it to do the job of a wide rectangle or a full triangle. If the attic needs a large air path, look at those shapes and still use the sizing notes.
A short sizing note
The piece shown is LOP1024, a 10 by 24 inch peak-top gable vent. Width is only 10 inches, and height is 24. The appearance range on the sizing page is about width versus gable width. On a large gable this vent will look like jewelry, which is sometimes what you want. If you wanted the vent to fill the peak, you want a triangle made for your pitch, not a taller peak top.
Pair it with
Pair it with a steep roof and restrained trim. A pointed window or a gothic arch nearby will agree with it. A house full of wide rectangles will make the peak top look imported. See the install overview before you cut a tall slot in the wall.