Trending Medium Length Cute Nails 2021 / Box nails are a holdover from when boxes were made from wood and the materials were thinner,(think fruit crates) and a thinner shaft minimized splitting of the slats when nailing. Box nails are the same length as their sinker and common sisters, but have thinner shafts. Medium Length Cute Nails 2021 - The silvery blue and purple locks offer a lovely iridescent effect that is beautifully ethereal.