Join two pieces of 1" OD round railing tubing at a square 90° angle without a welded joint. The 818-1 Perpendicular Collar slides over the tubing and locks the two at a right angle — the fitting for a cross-bar system, a partition rail, a smaller balustrade, or a light decorative interior handrail at the slimmer 1" size. It fits tubing with a.050" wall. Choose the finish that matches your rail: Polished Brass for a warm, traditional or heritage look, 304 Polished Stainless Steel for a bright modern finish, or 304 Satin for a softer, low-glare surface. It pairs with the matching 1" round tubing and fittings in the same line, so a rail comes together from parts made to fit each other.