Standard length is 16 inches but a longer length may be accommodated for an additional charge. All metal is solid sterling silver 925. Font size is 2mm-2.5mm depending on number of letters. Do be sure to indicate Grandma's special nickname for the heart charm. As much as my husband and children think that I am perfect (lol), I am far from it. Part of the charm of hand-crafted jewelry is the slight imperfections. As such, the letters will not be perfectly aligned nor identical. There will be some variance in spacing and appearance.