The Sheet Metal/HVAC Pro Calc is a versatile calculator that enables tradesmen to calculate complex problems with dedicated key functions that are labeled in standard industry terms. The calculator has other advanced built-in construction-math functions to enable HVAC and sheet metal tradesmen to do their work alongside other trades. In addition to the built-in functions, this calculator can handle order of operation, using the parenthesis operators. It can also perform square, cube, square root, and cube root calculations. Plus, it works as a regular calculator with typical symbols. The calculator can be used to determine ArcK constant for convenient Arc length solutions. And it has an offset functions for "S-shaped" bends in ductwork. It can also help solve the layout for wrapper length, centerline radius, and the angle. Features CUSTOM HVAC & SHEET METAL functions let you simplify Test and Balance (TAB) with built-in Fan Law function: CFM, RPM, SP and BHP; velocity and velocity pressure: FPM, VP, MPS, KPa; ArcK constant for convenient Arc length solutions; and offset functions FUNCTIONS AND TERMINOLOGY consistent with sheet metal and HVAC trade terminology; x, y, r (radius), theta and Seg Radius functions; works in and converts between feet-inch-fractions, decimal feet and inches and metric also converts between polar and rectangular coordinates PARENTHESIS OPERATORS allows you to easily enter complex formulas; order of operations calculations retain familiar mathematical hierarchy as a default preference; trigonometric operation and sequence; and you can calculate square, square root, cube, and cube root; easy non-90 triangles and right-angle solutions for ductwork length and angles MEMORY STORAGE conveniently stores frequently used constants or interim solutions; Memory swap lets you easily insert stored values into current calculations and simultaneously store calculated values while recalling and displaying Memory contents; other settable User Preferences INVALUABLE TRADE TOOL PAYS FOR ITSELF by reducing headaches, saving time, and preventing expensive material errors on all your projects. Comes with a rugged shock, dust and moisture-resistant Armadillo Gear protective case, quick reference guide and complete user's guide, a long-life battery, and a one-year limited warranty.