This durable two-sided plastic sizing wheel comes with a complete instruction manual for residential and commercial duct-sizing procedures. Designed by Hank Rutkowski.
- Sizes metal ducts, lined metal ducts duct board airways, and wire helix flexible ducts
- Converts round shapes to equivalent rectangles
- Correlates available pressure with total effective length and friction rate (Manual D sizing calculations)
- Converts velocity into velocity pressure and vice versa
- Corrects for altitude and temperature