The Ductulator - Duct Sizing Calculator is a hand held rotating calculator used for sizing supply and return duct systems using the equal friction design method. Includes scales for friction loss per unit length, air volume, air velocity, round duct diameter, and rectangular duct diameters. One side uses English units, the other side uses Metric units. Includes a protective sleeve with ASHRAE recommended design air velocities for system components/applications. Multicolorido, vermelho, verde e azul Um lado em inglês, um lado métrico, meerkleurig rood, groen en blauw. Lichtdoorlatende beschermhoes met ashrae aanbevolen design luchtvelocities Klassieke ductulatorstijl. Eén kant Engels, één kant metrisch ASIN B01BUGXB7G Size Small Color White Style Klassieke Material Plastic Batteries 1 Unknown batteries required. Item Weight 3.04 ounces Part Number TD1 Manufacturer Trane Power Source Battery Powered Display Style LED Item model number TD1 Batteries Included No Batteries Required No Product Dimensions 10.25 x 8.75 x 0.13 inches Item Package Quantity 1 Is Discontinued By Manufacturer No