National Hardware Smooth Rod, Series: 4055BC, 1/2 in Diameter, 36 in Height, Cold Rolled Steel, ASTM A510, Plain, For Fencing, Supports, Railing, Sign Posts, Frame Work and Other Industrial Applications. Designed For Fencing, Supports, Railing, Sign Posts, Frame Work And Other Industrial Applications. Excellent Forming And Welding Characteristics. Cold Rolled Products Have A Higher Yield Strength, Hardness And Tighter Specification Than Hot Rolled Steel. These rods have excellent forming and welding characteristics and are designed for many industrial applications. Material allows more precise diameter compared to hot rolled steel rods. National catalog model.