Manufactured from mild steel, Columbia-MBF’s Rigid Conduit is highly resistant to damage from impact yet ductile to facilitate bending. The 3/4" taper NPT threads (ANSI B1.20.1) are full cut and hot galvanized after cutting. Color-coded end cap thread protectors keep the threads clean, sharp and also provide instant trade size recognition. Even sizes are color-coded blue, 1/2 sizes black, and 1/4 sizes red.