Two-inch tubing is the guard rail size, and it puts more load into every mount. The 530/2 wall flange is built to carry it: a deep collar holds the 2-inch OD tube, a set screw locks it, and a pre-drilled base takes the wall fasteners. The result is a rail end that stays square through years of leaning and bumping. Two finish families cover the likely projects. Polished brass suits a restored guard rail or a brass cap-rail run, and it develops a natural patina that polishes back when wanted. 316 stainless, polished or satin, is the choice for exterior, pool-side, and coastal installations, where the marine grade resists chloride pitting. For a corner or column return that will not clear the round base, the Cut Wall Flange 531/2 keeps the same collar in a trimmed footprint. Ships from US inventory.