The Dayton Audio H08RW high-frequency waveguide is precision-molded from rugged ABS plastic and features a standard 1-3/8" - 18TPI screw thread for easy mounting on matching speakers. It provides a sound with less distortion and a nice opening. Dayton Audio waveguides reveal the full articulation and precision of sound reproduction that your HF speakers are capable of delivering. The H08RW is designed to have a 75° cone format and provide a useful acoustic load up to 2200Hz.