APOGEE-AFI-4WB w/Gas-tight Barrier Strip APOGEE-AFI-4WB w/Gas-tight Barrier Strip - The AFI-4 can be ordered with a 60º x 45º or a 90º x 45º rotatable high frequency horn. This allows the loudspeaker to be installed in either a vertical or horizontal position without compromising optimum coverage. An added benefit of the rotating horn is exceptionally tight pattern control in both axes, due to the symmetrical shape of the horn's perimeter.