Tested and working Construction Master IV calculator by Calculated Industries. Comes with heavy-duty Armadillo Gear protective hard case. Preowned with light wear. Perfect for construction, contractors, or framing work. Features inch/feet conversions, diagonal calculations, stair layout more. Thanks so much for visiting my store! I happily accept offers on most items?just click ?Make Offer!? Please note: I do not ship on weekends or holidays. Have any questions? I?m happy to help! Be sure to check out my other listings for more unique finds!