Conduit hanger with carriage bolt & nut, for 1-1/2 rigid, use to secure & suspend rigid conduit, imc, electrical metallic tubing or pvc conduit from overhead supports, slotted carriage bolt frees both hands for installation, each part is stamped with trad e size markings. Conduit Size-Rigid/Pipe/EMT/IMC (inches) 1 1/2 Material: Steel Finish Electro-Galvanized Can be Used for Either Vertical or Horizontal Installation. 6HTB Series have a built-in nut so there are less parts to handle or drop Installs easily with a screwdriver