This is a pack of two bone nut blanks perfect for cigar box guitars and other homemade instruments. Here are the dimensions: Length: 1.536" (39mm); Height: 0.350" (9mm); Thickness: 0.195" (5mm) These nut blanks are made from cow bone and are perfectly rectangular in shape. You will need to file/shape them to your needs and add string notches as desired.