TUSQ’s 1.69" slotted nut is specially designed to be used on Martin style guitars and others with similar specifications. TUSQ nuts have a harmonically rich tone without the inconsistencies found in ivory, bone or other natural materials. Where bone and ivory have varying grains throughout each piece, hampering consistent transfer of vibrations to the guitar top, TUSQ nuts have been designed to transfer the right frequencies more efficiently from the strings to the body of the guitar.