This interlocking heavy duty swaged mast system is perfect for site work where the required height may be unknown until the actual installation takes place. The design allows easy handling, shipping, and storage and yet enables up to 3 mast sections to be locked together on site. The steel mast is zinc passivated for corrosion protection. The swaged ends have shaped interlocking slots with three flutes to prevent the mast section turning when assembled. This stops the aerial moving out of alignment in high winds.