The BA90 bracket is for either flat or extruded street name signs and designed to mount on a U Channel sign post. The BA90 bracket has a 5 ½” slot length and holds your street name at 90 degrees. (perpendicular to stop sign). A small hole is drilled on each side of the slot and tapped to accept a 5/16” set screw. All brackets come with standard set screws and all necessary mounting hardware.