I picked up a cool yagi free The boom is 51"-it's 4 elements: main flat-oval element is 36".....rear element is 41".......and the two front elements are 36". The mounting holes at the end of the boom behind the 41" rear element give you the option of mounting with elements vertical or horizontal. I connected this thing to the scanner inside the house and it has very potent reception! Connot wait for the chance to get it up on the roof. Obviously it's directional (right?) but I wonder how to mount it for best performance-vertical or horizontal. I wonder if vertical makes it omnidirectional?? Thank you people!!