Please be advised that the OPENING DIMENSION is going to give us the most accurate measurement for that part.
The door opening dimensions can be measured by measuring the distance between the inside point at the jamb from one side of the opening to the other.
We have two versions of the SNAP-IN GASKET. One is for our FRP Doors and has 3-darts. The other is a single-dart SNAP-IN GASKET. Please see attached photo. The one on the left is the FRP and the one in the center is the single-dart snap in. The one on the right is our SCREW-ON GASKET.