Kit necessary if planning to surface mount rather than installing in between studs.
60" Trim Kit used for Model A-46 & AL-42
48" Trim Kit used if purchasing Model A-42, E-342, NE-342
No trim kit necessary for Model NE-242
Trim kit finishes out sides of unit for flush finish. Trim pieces can be stained or painted to match cabinet. Unit will protrude approximate 7" to 8" rather than 3" - 4" depending on which model purchased.