Overview The Construction Master Pro is an award-winning advanced feet-inch-fraction construction-math calculator with powerful built-in solutions for completing layouts, plans, bids, and estimates. The Construction Master Pro allows you to calculate circles, roofs, stairs, and more. It works in and converts between feet-inches-fractions and decimals, including metric. Use the calculator in the office or the field to save time, cut costs, prevent re-work and maximize profits. Work in and convert between building dimensions, including Metric Built-in Right-Angle solutions Areas, Volumes, Square-ups Complete Stair Layouts Roof, Rafter and Framing solutions Circle: Arcs, Circumference, Segments Drywall: Siding and Panels Stairs: Riser Height and solve for Stair Openings Studs On-center Compound Miter Cuts Arched Rake-Walls Who's It For? Contractors Estimators Architects Carpenters Framers Draftpersons Engineers Builders Tradespersons Specifications Size: 5.7" x 3.0" x 0.65" (145mm x 76mm x 17mm) Product Weight: 4.6 oz (130g) Includes case and Pocket Reference Guide Power: Two 1.5-Volt LR-44/A76 long-life batteries Display Type: 11 digits (7 Normal, 4 Fractions) Display Dimensions: 0.625" x 2.5" (16mm x 63.5mm) Accuracy: 12 digit internal accuracy