1/2 in. Rigid 1-Hole Conduit Straps (100-Pack)Where load bearing is required, use these 1 2 in. 1 Hole Conduit Straps (100 Pack) to secure IMC and rigid conduit to surfaces such as wood and masonry. They are made of steel and electro plated with zinc for corrosion resistance. These conduit straps may be used indoor or outdoor. Secures IMC and rigid conduit to surfaces such as wood or masonry where greater load bearing is required Zinc plated steel for corrosion resistance UL and CSA Listed