Set a 1.5" OD railing post to the floor with the strongest connection in the line. The tube comes permanently welded to the flange, so the post and base are one piece with no slip-fit joint to loosen over time. That makes it the right base for a post on an outdoor deck, a pool surround, a coastal terrace, or any run where the mount has to stay tight under weather and use. It's 316-grade satin stainless steel, so the marine-grade chloride resistance holds up outdoors and near salt air, and the satin finish hides the welds. Because it ships as a pre-fabricated assembly, there's less to do on site. For an indoor rail or a decorative base, look at the regular slip-fit floor flange instead. A spec sheet is available for code-compliance documentation.