The Aluminum Post Kits makes installation simple. The 3"x3" (.125" thick) post kits are black in color and available an a range of sizes. Each post includes a post cap, 2-piece post skirt, and has a fully welded base plate for mounting to the surface of the decking (additional blocking and mounting hardware is required). For 36" tall railing use 38" posts for straight runs and 44" posts for each side of the stairs. For 42" tall railing, use 44" posts for straight runs and 54" posts for each side of the stairs. The posts may be trimmed down as needed on site. Fasteners are not included for installing to the decking or concrete surface.