Accepts masts up to 1-1/2" OD maximum 14 Gauge Feet, 18 Gauge Tube. Designed to mount telescoping masts on flat or peaked roofs. Allows tall masts to be swung up along the ridge of the roof mast Mast is held securely in place with 2 heavy duty set screws ((GUY WIRE, LAG SCREWS, AND GUY SUPPORTS ARE NOT INCLUDED. THE MANUFACTURER DOES NOT PROVIDE INSTRUCTIONS FOR THIS ITEM))