Stanley 24" Aluminum English Carpenter's SquareThis STANLEY 24 in. Aluminum English Carpenter's Square is a versatile tool providing a wide range of easy to read English measurement scales, tables, and conversions, including the new lumber scale, decimal equivalent table, and metric conversion table; formula for squaring a foundation; 45 degree, 60 degree, and 30 degree angle markings; volume and area formulas; wood screw gauge table; drill and nail sizes (common and finish); quantity per pound;