This popular style is used in the majority of installations in the United States, Alaska, and Canada. Rust-resistant zinc-plated cast-iron design. Each cap is designed with a 30 mesh screen to prevent debris from entering the vent pipe. No. 14023: Material Type: Cast Iron, Finish: Zinc-plated, Screen Size: 30 mesh, NPT: 1-1/4in Female No. 14024: Material Type: Cast Iron, Finish: Zinc-plated, Screen Size: 30 mesh, NPT: 1-1/2in Female No. 14025: Material Type: Cast Iron, Finish: Zinc-plated, Screen Size: 30 mesh, NPT: 2in Female