This mechanical calculating machine is all metal and is 11 3/4" long x 2 1/2" wide. We are told this could be from 1920-1930 or earlier. It calculates dollars in cents up to ten thousands (6 digits with cents) There is a zeroing mechansm lever on the left side that also works. It has a few scratches. The wheels have light rust but turn and work. There was a stylus that came with the piece when new to turn the wheels. A pen works find or similar. The back has green felt for desk protection.