https://www.amazon.com/dp/B00432S99U/
Attached photo: what is the metal mounting piece called? It says "fit any standard
pole up to 4 inches in diameter", but I need to attache it to
rectangular front porch metal pillar (4 inches by 4 inches), I guess I need to buy a longer metal mounting piece.
By the way, is it okay to install it on
rectangular pillar?
Thanks.