The frame is adjustable for jamb sizes ranging from 4-9/16" to 6-13/16".
For smaller jambs (Sample B) the "J" jamb needs to be cut.
Two mull casing options are available. Standard mull and 1-1/2" Spread mull casing.
Spread mull casing is used for 2x construction between units.
This option adds strength and structural integrity.