We recommend a minimum of 6×6″ timber post or 5.5″ outside diameter Steel post with a 1/4″ wall. Your posts should have a footing of a minimum 18″ x 4′ down with concrete (in compact, non-virgin soil). It should be noted this sizing recommendation will accommodate most of our standard sized sails. When considering larger Sails, you should consult with us or a local engineer to determine your needs. The finish of your posts is mostly down to personal preference, there are several options you could consider; you could galvanize your posts, paint or powder coat them.