EASILY ADJUST Your Antenna to Any Desired Angle & Position for Optimum Signal Reception - Tilts and Swivels in 2 Directions UNIQUE MOUNTING PLATE Hole Pattern Fits Most Outdoor Antenna Mounting Bolt Positions MOVEABLE BRACKET LOCKS INTO POSITION by Tightening the Nuts on the Ends of the Arm PERFECT FOR DIRECTIONAL ANTENNAS such as Yagi, LPDA, Grid and Panel Styles DURABLE CAST ALUMINUM Construction Resists Rust and Corrosion - Suitable for Outdoor and Marine Use FOR EXACT HOLE POSITIONS see the "Instructions For Use PDF" link in the Product Guides and Documents section of this listing below