Morris Products 17474 Support Beam Clamp, Mallable, Iron, 3/8"-16 Rod Size, 1/2"-13 Set Screw Size, 525 lbs Max Load Mallable Iron Rod Support Beam Clamp - Strong, durable Rod Support Beam Clamp. Used with Conduit Hangers, Bridle Rings & Drop Rods 1/4" up to 1/2" Tapped for Rods - bottom and back on all sizes Malleable Iron Zinc Plated