Ubiquiti Networks airMA Yagi Antenna - Manual (Page 6)

4. Attach the antenna to the pole.
Note: The mounting assembly can accommodate a
Ø 1.25" - 2.25" pole.
a. Insert the two U Bolts into the Main Mounting Bracket of
the antenna.
b. Secure each U Bolt with two Serrated Flange Nuts.
c. Tighten all nuts to approximately 25 N-m (18 lb-ft) or
less to avoid deforming the pole.