MX-nail This nail is especially suited for those horses with very sensitive or thin hoof walls. The ultra slim MX nail is designed to reduce hoof wall displacement to a maximum and to provide a very smooth and accurate drive of the nail. Precision, accuracy and reliability are key features of all our nails, the error margins of Mustad nails is minimal. To aid in the right placement of the nail, the Mustad M is always placed on the same side