ASTM A394 Tower Step Bolts ASTM A394 is a standard material specification covering chemical and mechanical requirements of hexagon and square-head zinc-coated steel bolts and atmosphericcorrosion-resistant bolts, in nominal thread diameters of 1⁄2, 5⁄8, 3⁄4, 7⁄8 and 1 in. for use in the construction of transmission towers, substations, and similar steel structures. Yokelink Tower Step Bolts are used to climb poles and electrical transmission towers. Each assembly includes one ASTM A394 Type O Step Bolt and two ASTM A563 Hex Nuts. The high strength Tower pole step bolts also available..All parts are galvanized in accordance with ASTM A153. Galvanized plating protects the bolt from corrosion; typically used in outdoor applications.. Other lengths and 1 inch diameter ASTM A394 Step Bolts are available. When you need Tower Step Bolts, refer to above our catalo…