Advanced construction math calculator with trigonometric functions for engineering and building professionals. Determine precise angle measurements and solve the most complex design and construction math problems. Functions are built-in: stair calculations, common rafters, jack rafter key, circular key, rake-wall key. You can also quickly estimate board feet. Added features: User preferences, exponential notation, backspace to change “justentered” values, constant operator, cost per unit and paperless tape to review the last 20 entries. Operate it as a standard math calculator. Comes complete with protective hard cover, easy-tofollow user’s guide, pocket reference guide, long-life batteries and full 1-year warranty.