There are 3 basic louver profiles.
1 - Standard Jamb: The louver box, or jamb is 3" deep overall. The louvers are mounted at the standard 30deg. and the face trim is mounted to the surface of the jamb.
2 - Surface Mount: The louver box, or jamb is minimized to 1 1/4". Louver blades are 2 3/4" wide set at 30deg. Face trim is recessed to 1/4" giving the entire unit an overall depth of 1 1/2".
3 - Closed Louver: This design will not vent. The louver blades are mounted so as to rest one upon the other. Overall unit depth is 1 1/4".