1, product description * name:secondary rack * material: steel ect. * surface finish:hdg or customer's need Secondary rack comes in three different class and type of application, either single, two or three spool type for light, medium and heavy duty class respectively. Insulator post struts are rounded to assure it will not damage insulation when stringing secondary. Struts are electricity arc welded adn riveted for heavy and medium duty class respectively. Ansi class 52-3 and 52-2 insulator will fit the heavy and medium duty rack respectively.