Keep in mind - if you are mounting them to a building you very much need to add an oversize plate to spread the load. Regular pole brackets are too small. When mounted directly to masonary/brick they WILL begin to move a small amount and get loose. Eventually they will fall - and sometimes take chuncks of brick/concrete with them. The mounting surface area is just too small. The one signpost-boston added a picture of has a proper plate to distribute the load.
I've personally gone and replaced regular ones mounted directly to walls by someone else for the Dept of Defense at a military base. They had only been up a year and all were coming loose. They used proper anchors and everything.... The military was very unhappy about it as one of them did hit someone when it finally came loose.
We replaced them with ones from Kalamazoo Banner Works. Used their airow poles with their wall plates. They prebuild them - very nice quality but not the cheapest.
